Title: Do Not Argue
Author: fanficwriter101
Pairing: Mycroft/Lestrade
Fandoms: Sherlock
Disclaimer: The characters from the show aren't mine, they belong to others. No copyright infringement intended. Any characters you don't recognize are mine. Feedback would be nice, positive feedback would be nicer. Enjoy!

Category: Sherlock (BBC 2010/12 version) Mystrade slash (implied) fic

Rating: R to be safe for content not topic

Characters: Ensemble plus some OFC's and OMC's

Series: No

Spoilers: None intended but anything from Seasons One and Two (including the unaired pilot) might get a mention.

Summary: Secrets were a fact of life and something they rarely thought about. Until that letter arrived...

Archive: Just tell me where it's going

Additional 'stuff': I've had this female character in my mind quite some time. From some checking I've done, there aren't a large number of these kinds of fic out there.

This is from ASIB - this fic fits in near this scene (where Mycroft 'tempts' Sherlock with a cigarette then later smokes himself):

Sherlock: Do you ever wonder if there's something wrong with us?
Mycroft: All lives end. All hearts are broken. Caring is not an advantage, Sherlock.
Sherlock: This is low tar.
Mycroft: Well, you barely knew her.

***

**Two months earlier...**

Mycroft often lamented - mostly inwardly - the new preference for e-mail communication rather than proper pen and paper letters. So a letter in a familiar handwriting which was addressed to him at his office was a pleasant surprise. He read the letter - from an old friend from University - and considered the suggestion - lunch or dinner in the next few days. He checked his diary and called the number on the letter to make the arrangements.

Elizabeth Butler had been, for almost two terms, the woman who had shared his life - and, briefly, his bed - before the evening where she forced Mycroft to sit down and admit that marriage and children didn't hold the interest for him that it did for her.

Lunch was pleasant and conversation was easy and light. Mycroft had followed her career with apparently casual interest and they discussed her work in the Hague before she reached out and covered his hand with her own.
Mycroft was a little surprised at the intimate gesture but didn't let his discomfiture show on his face.

"I won't waste time. I am dying." She saw Mycroft's reaction to her unexpected news and realized he hadn't known. As he began to form a reply, she interrupted: "No...please...let me finish."

Mycroft nodded and sat back.

"Michael has just begun a junior post in the FCO. I would like you to...keep an eye on him."

Mycroft nodded. "Of course."

"I would prefer he wasn't posted to a warzone although I don't expect you to be able to influence..."

Mycroft smiled and squeezed her hand gently. "I believe his first overseas post will be in Western Europe."

Elizabeth laughed softly. "So Harry was right. You really do have the ear of the..."

Mycroft coughed, embarrassed, silencing Elizabeth in mid-sentence. "You have no need to worry for your son's safety. You have my word."

Relieved, Elizabeth changed the subject. "How is Harry...I speak to him so rarely now."

Mycroft smiled, relaxing. "I saw him only a few weeks ago. Sherlock was able to be of assistance to...in...a delicate situation."

"How is your brother? Still a nightmare?"

"No, in fact. He has a new flat, a new flatmate and is much less...troublesome."

Elizabeth smiled and sat back, picking up the menu. "Now...dessert."

Mycroft licked his lips and picked up the small piece of paper. "Why not."

************

**Eight days earlier...**

"Sir...Mr Cavanaugh for you."

Mycroft took the phone from his assistant. "Harry?"

"She's dead Mycroft. Lizzie's dead."

Mycroft shuddered, almost dropping the phone but gathered himself within a few moments. "I'm sorry Harry."

"Where are you? The funeral's tomorrow."

Mycroft closed his eyes. "I'm afraid I can't attend."

They chatted for a few more minutes during which Mycroft battled tears. His assistant slipped her hand lightly onto her boss's back and steered him into a quiet alcove in the busy meeting room.

As he handed his assistant the phone, they both pretended they hadn't noticed either his shaking hand or his glistening eyes. His assistant pretended she hadn't seen him bring a cigarette packet from his jacket before realizing that he was indoors and couldn't smoke.

***********

**The previous day...**

Mycroft got into the back of the car which had been waiting for him as his plane taxied to a stop close to the terminal building. Thankfully his position meant he didn't have to do anything as tedious as wait for luggage or queue to have his passport examined. He leaned forward and spoke to the driver, requesting a stop on the way home.

Mycroft climbed out of the car and walked across the graveyard stopping beside a freshly-covered grave. He spent only a few minutes, conscious of the driver's interest in his passenger's unexpected request to stop at the churchyard.

When Mycroft eventually arrived home, Greg was, he was disconcerted to discover, waiting up for him despite the late hour.

Greg's nose wrinkled as he made Mycroft some tea. "You smoked. Sherlock's given up and you're starting."

Mycroft took the tea and sipped the hot liquid slowly, playing for time. "A friend died. I went to the grave to pay my respects."

Greg walked over and put his hand on Mycroft's. "Do you want to talk about it?"

Mycroft sighed. "No, thank you. I'm going to have a bath."

"How was the meeting?"

Mycroft shook his head tiredly. "Dreadful. There is only one outcome of this financial mess and it won't end happily for any of the countries involved."

Greg nodded and offered: "If you want to get in the bath I can make you something to eat?"

Mycroft smiled and shook his head. "Thank you. I ate on the plane."

"Yeah, right. I'll make you something that'll taste better than the plate it was served on."

Mycroft was both too tired and too experienced in arguing with his partner to bother protesting and headed into the bathroom to start the bath running before walking into the bedroom.

************************

**Present day...**

Greg was waiting for the toast to brown while Mycroft sorted the day's post which had just been delivered. Greg had had to get used to the fact that their post was x-rayed and examined before it even arrived at the flat. He no longer even thought about it as Mycroft had explained it was a necessary delay unless Greg wanted to collect his post every day from Mycroft's office.

Greg didn't let on that he had seen Mycroft tucked one of the letters - a hand-addressed cream envelope - into his jacket before bringing the remaining letters over to the kitchen counter. "Anything interesting?"

Mycroft sighed and flicked through the assorted size and colour envelopes.
"Bills...invitations to upgrade our television and telephone packages...oh...the new season's programme for the Royal Opera House and...you have a letter from your alma mater."

Greg tore the envelope with his school's crest printed in the top right-hand corner open and laughed softly as he read the letter inside.

 "What is it?"

"My school's inviting donations for a new science block."

"Oh, well, we should make some...contribution."

Greg shook his head. "I don't think so."

Mycroft frowned. "Why not?"

"I have to go to work..." Greg huffed and made a big show of looking at his watch and leaving a half-eaten piece of toast on the plate.

"Greg?" Mycroft probed gently.

"I'll see you later."

Greg was out of the door before Mycroft could ascertain the reason for his partner's sudden change of mood. That didn't mean he forgot about it.

**Later that evening...**

Mycroft had prepared a peasant stew - beef, vegetables, wine all left to simmer for a couple of hours until the meat was meltingly soft - and opened one of their better bottles of red wine to let it breathe.

Greg could smell the food as he approached the door, sliding his key into the lock and opening the door, standing in the doorway for a moment or two, just inhaling the amazing aroma before letting himself into the flat.

His eyes were drawn to the coffee table where a letter, expensive cream stationery, sat unfolded.

"You got that this morning."

Mycroft heard Greg and walked over from the kitchen wiping his hands on a cloth.

"Yes. I wanted to confirm some of the details before I discussed it with you."

Greg fought a rising sense of unease bordering on panic and snatched the letter up, skimming the content quickly. "Bloody hell Myc!"

"It would appear I may be..."

"Some kid's dad." Greg finished his partner's sentence.

Mycroft bought two half-filled wine glasses over from the kitchen and handed one to Greg.

"Did you know this woman...twenty years ago?"

Mycroft nodded. "Twenty-two years in fact. My last year at Cambridge. We were..."

"Lovers." Greg said uneasily.

Mycroft sipped his wine, knowing Greg well enough to know that wasn't the end of the conversation.

"DNA...you've had a DNA test and this boy..."

"Michael." Mycroft supplied.

Greg very nearly rolled his eyes.

"...is definitely yours."

"I wanted to discuss this with you before undergoing any medical procedures."

Greg took a large sip of wine, sighed, dropped the letter onto the kitchen counter and looked over at the large pan hissing softly on the hob. "What's for dinner?"

"Boeuf bourguignon." Mycroft said, glancing over at the stew.

Greg's wine glass was almost empty and he walked across, refilled it and turned the hob down to its lowest setting. "Why aren't you more...I dunno...surprised? Have you known for a while?"

Mycroft decided not to lie. "Elizabeth wrote to me two months ago. We met for lunch. She told me she was unwell and she wanted me to...keep an eye...on Michael. I didn't know he was mine until today."

"You still don't." Greg pointed out. "You said you hadn't had a test. And why wouldn't she tell you then?"

Mycroft smiled a little. "Probably because I told her about you."

"Is this ready?" Greg stirred the stew.

Mycroft nodded and laid two places on the dining room table.

Greg wasn't sure what he thought about this new...thing...in their relationship. He fell back on his usual comforts - well, two of the three - and drank some more wine and began to serve the stew.

Mycroft hadn't had any idea how Greg would react to his news and he still wasn't sure. Slyly, he decided a change of subject was called for. "So...we should decide on an appropriate donation to your school."

Greg almost cracked the plate with the force he slammed his fork down. "They're not getting a penny, okay!"

"Did you get a bad mark in a biology test?" Mycroft pushed, experiencing an all-too-rare feeling of schadenfraude at his partner's discomfiture.

Greg took a large sip of wine and picked up his fork. "I liked sports. Hated science. If they wanted money for a new...I dunno...sports hall...fine, but science, no way." He scowled when he saw Mycroft's smile. "What?!"

"I was the exact opposite."

Greg sighed and smiled too. "Shocker."

The two men laughed and Mycroft threw Greg's cheque book at him. "Donate."

Greg hesitated only a heartbeat. "Like you did or with some money?"

Mycroft frowned, not understanding then as he saw Greg's grin he caught up and threw a linen napkin at Greg.

*************

An hour later, he was no nearer knowing. They hadn't discussed it further and he was a little disappointed Greg wasn't more interested, spending most of the meal complaining about Sherlock's comments at a crime scene earlier in the day.

***************

Two hours later Mycroft couldn't let it go. Greg was in the bedroom undressing for a bath which was already running. He walked into the bathroom and sat on the edge of the bath. A couple of minutes later Greg joined him, a towel around his waist. "Myc?"

"You're angry. I'm not sure why. Please tell me."

Greg frowned. "You're brainy. Work it out. Is it that you never told me about this woman you slept with or that you had a kid or maybe you didn't but you're too chicken to get a DNA test or that it changes just about everything?"

Mycroft got up. "It doesn't change anything."

Greg pulled the towel off, dropping it on the floor, and climbed into the bath. "If you really think that then maybe you're not as clever as I thought you were."

Mycroft left the bathroom, closing the door behind him.

*********

Greg spent as long as he could in the bathroom letting the water get cold although he hardly noticed until he began to shiver.

Walking into the bedroom he didn't speak until he'd taken off his bathrobe and changed into soft grey boxers when he realized he had to decide if he was going to spend the night in the spare room.

As if he had anticipated Greg's dilemma, Mycroft said sadly: "I put fresh sheets on the spare bed."

"I want to meet her."

Mycroft swallowed hard. "She died eight days ago."

"You were in Greece eight days ago."

Mycroft nodded. "I wasn't able to fly back for the funeral."

"So the kid was on his own?"

"I imagine there were other family members in attendance."

"But not his dad."

"I may not be..."

"She wouldn't have had lunch with you after all that time just because she was bored."

Mycroft nodded. "The DNA test currently available isn't absolute proof the child is mine. It will prove definitive only if he is not."

"I'm a copper Myc. I know how DNA tests work."

Mycroft smiled apologetically. "Of course. I'll arrange the test tomorrow if the boy consents."

"Michael."

"I'm sorry?"

"The kid's called Michael." Greg said, walking over to the bed, sitting down.

"I'm perfectly well aware..." Mycroft saw Greg's face and paused mid-sentence.

"Have you told Sherlock? Or John?"

"No. Not yet. I want to be certain of the test result first."

"Either way, I'd like to meet him."

"Really?" Mycroft looked surprised.

"Yeah." Reckon his mum must have told him what you were like at his age."

Mycroft groaned and slid down until completely covered by the bedclothes.

Greg laughed for the first time that evening and climbed onto the bed, prodding the duvet-covered lump which could have been any part of Mycroft none-too-gently until he got a satisfying squeak of surprise and discomfort.

"That's for not telling me you'd had a girlfriend."

Mycroft lowered the bedclothes just far enough to expose his face. "It was one term. Twenty years ago. Have you told me everything you did when you were that age?"

"Yes." Greg said. "Either that or if there was something I forgot I'm sure someone's told you about it."

Mycroft refused to be embarrassed at Greg's comment. There was actually nothing he hadn't known about his new boyfriend when they first began to date properly even though he had forgotten most of it.

"What does he look like?"

Mycroft stretched out an arm under the bedclothes until his hand closed around his blackberry. Turning it on Mycroft brought up a picture of a young man in a graduation gown and mortar board. He handed the phone to Greg.

Greg had guessed Mycroft would have pictures of the boy but he was struck by one thing. He had seen pictures of Mycroft at his own graduation. The physical similarity between his partner and the boy was unmissable. He knew from the look on Mycroft's face as he handed the phone across that he knew it too.

Greg crawled under the bedclothes as he handed the phone back to Mycroft. "I've got a departmental meeting tomorrow morning. Should be finished by eleven-thirty."

"I'll speak to Michael tomorrow." Mycroft promised.

As he reached to turn the light off, Greg mused: "We might be dads."

Mycroft sighed and turned onto his side, sleeping fitfully for the next six hours.

************

**The following day**

Molly Hooper had just finished her first coffee of the morning and was beginning to set out the things she would need for her day when the door opened and she turned, smiling, as she saw John Watson. Because John usually meant Sherlock. She hoped her disappointment didn't show when she realized John had bought a Holmes with him but not Sherlock.

"Molly...morning.  Could you do me...us...a favour?" He opened a small insulated box and passed it over to her.

Molly took the two small vials and looked back expectantly at John. "What test do you want me to run?"

"DNA."

Molly frowned at John then tried not to look at Sherlock's brother who stood, leaning on his umbrella, in the doorway of her lab.

*****************

The test was, as Mycroft expected, over all too quickly.

"Well, whoever they are, they're a match. I mean...they're related. It's too close to be anything else."

Molly held up the two printed sheets and showed John, keeping away from the tall man in the doorway.

"Thank you Molly."

"Is...is Sherlock going to be coming here today...at all?"

John smiled. "I'm sure he'll drop in Molly."

Molly smiled and turned away.

**********************

Mycroft walked slowly out of the morgue and the only sound was the tap-tap of his umbrella as John followed him outside.

"Who are you going to tell first?" John broke the silence as they reached the side entrance of the building.

Mycroft held the door open for John. "I really have absolutely no idea."

John frowned. One of the things he could rely on was the Holmes' certainty. This was worryingly unexpected. "Would you like to get coffee or something?"

Mycroft smiled gratefully. "Thank you."

John walked a little ahead, guiding Mycroft to a nearby café.

*********************

Later that evening...

Greg looked up every single time the restaurant door opened. In contrast, Mycroft seemed unconcerned by the wait for their guest, sipping water between taking, and making, calls.

Finally, just as Greg was about to order a second drink, the Maitre'd showed a young man over to their table. "Your guest has arrived Mr Holmes."

Mycroft stood and waved a hand at Greg. "Michael, this is Detective Inspector Gregory Lestrade. Greg, this is Michael Butler."

Greg got to his feet and shook the younger man's hand. "Good to meet you."

Michael smiled nervously. "Sorry I'm late...I had a briefing..." He sensed Mycroft's irritation at his tardy arrival and sat down in mid-sentence.

"Yeah, we both know what that's like, might Myc?" Greg said with a stern look at Mycroft.

Mycroft forced a tight smile and the briefest of nods.

Greg handed Michael a menu. "Mycroft says you're working at the Foreign Office. Must be interesting."

The meal progressed with Mycroft practically silent unless Greg pressed him for a response. Michael sensed the atmosphere and was clearly uncomfortable.  After the main courses had been cleared away, he excused himself and headed for the bathroom.

"What the hell is wrong with you?!" Greg hissed. "Poor kid's just lost him mum and you're behaving like it's his fault you used his mum as an experiment to be sure you were gay!"

Mycroft's eyes blazed angrily and his mouth settled into a tight line. Through gritted teeth he muttered: "It wasn't like that!"

"If you don't want to be here, just go." Greg jerked his head towards the door.

"Fine." Mycroft signalled the waiter, handed over enough cash to cover the meal and a large tip and as he pushed his wallet back into his jacket, he pulled out the two DNA test result sheets and dropped them onto the table.

"Harry Cavenaugh."

Greg frowned and looked at the two sheets without being able to interpret what they showed. "Who?"

"Harry Cavenaugh. The man Lizzie turned to after we...after I..."

"He's Michael's dad?"

Mycroft nodded and left the restaurant moments before Michael returned.

Greg groaned inwardly as the young man looked around the room. "Yeah, he had go to...some international emergency."

"Oh...okay...Mum always said Mr Holmes had some important job in the Government."

Greg smiled. "Yeah. So...dessert?"

Michael picked up the menu and uncovered the two DNA test results. "Mum told me. About her and Mr Holmes. He's not my dad though is he?"

Greg shook his head. "Did she ever talk about someone called Harry?"

"Yeah, he works in the Royal Household. He's equerry to..."

Greg nodded. "It turns out he's...well, the test showed he..."

"I sort of wanted it to be Mr Holmes."

Greg smiled sadly. "So did he."

**Three days later**

Greg picked up the envelope with his school crest printed on it and opened it, wondering what they wanted this time.

He read the letter and walked into the bathroom where Mycroft was cleaning his teeth. "This is a letter from my old school. Thanking me for my donation.  Apparently they had a large anonymous donation which was enough to pay for the final bit of the science block so they decided to re-turf the rugby pitch."

Mycroft rinsed his mouth out and dried his face. "That's nice."

Greg stared at Mycroft with one eyebrow raised. "Anonymous?"

Mycroft smiled and took the letter from Greg. "Completely untraceable."

Greg laughed and headed out to work.

End

***