I own nothing except my own imagination. This story was inspired by this headcanon: post/27061751263/submitted-by-anon-submit-your-headcanons-here

"No, no! Get away from me!"

"Mummy -"

"I never want to see you again, Siger! I told you after the last hussy - never again. Get out!"

"I'm not Siger, Mummy. It's me, Mycroft."

"No!"

Mycroft tries once more to take her hand, but she slaps it away, shrinking from his touch, recoiling into the violet silk dressing gown he gave her last Christmas. She looks painfully young, dwarfed by the overstuffed armchair he brought from her room in the house. The Alzheimer's had made her almost childlike. Mycroft forces himself to remember this. He certainly has experience dealing with unreasonable children.

"Now, Mummy, be calm. We can -"

"No, no, no! Go away!"

She's crying. Mycroft leans back, helpless. An attendant, a sweet-faced blonde bleeding-heart, dashes into the room.

"Shh, now," she says, putting her arm around the older woman's shoulders. "It's alright. It's alright."

"Sarah, I want him gone."

It's the final straw. She knows this girl's name, but can't recall… Mycroft stands before the girl can meet his eyes and does an about face, prepare to walk away. Sherlock is standing in the doorway.

He is completely still except for his eyes, which dart from Mummy, who is patting her eyes dry on the silk sleeve, to the bleeding-heart who is comforting her with murmuring nonsense, to his older brother, who is no doubt looking uncharacteristically out of control.

It has been months since Sherlock bothered to come visit Mummy. Mycroft knows the absolute terror that accompanies seeing their mother's mind decay, but Sherlock seems not to have found a safeguard against it. Easier for everyone, particularly Mycroft, if he just stays away. Of all the days for him to decide to be dutiful…

"Sherlock!"

It's Mummy, and she's looking at her younger son as if he's some angelic vision from on high. Sherlock goes to her, doing Mycroft the courtesy of not looking at him as he does so.

"Yes, Mummy?"

"It's been ages since you've come home. How is school? Have you made any friends?"

Mycroft waits only long enough to hear Sherlock begin to stammer some sort of reply before exiting the room.

Sherlock. The favorite son. The one who inherited her musical talent, chameleon eyes, dark curls, and not a scrap of her husband. Sherlock had been Mummy's consolation for having a miniature Siger as a first son. It doesn't matter she apparently thinks he's still 12. She's held on to his memory, probably fought to keep it.

Mycroft finds himself outside the facility, reaching for the cigarettes in his coat, without quite knowing how he got there. He's not a habitual smoker. He actually started to show Sherlock it was possible to control one's use of an addictive substance. It would be poor judgement to smoke one now, but he puts it to his lips anyway.

"Is it low tar?" Sherlock asks from behind him.

Mycroft lets the flame in the lighter go out and turns to face him. "No, actually," he says, his voice perfectly calm.

"She's calmed down."

"Good."

They stand in silence. Sherlock reaches for his own pack and lights up, then offers the flame to Mycroft. The first puff reminds him why he usually chooses low-tar, but he resists the urge to cough.

"Listen, Mycroft -"

"I beg you, brother, don't attempt to explain it. I look like him. Almost exactly like him. It's natural for her to be confused. I don't take it personally."

"I was going to ask if I could have access to the MI5 files from last month. I need data for a case I'm working."

"Liar."

"Should I take that as a no? You know I can easily hack the system."

"And I'll easily stop you."

"You're not like him."

It isn't the comeback he was expecting. Mycroft coughs out the smoke in his lungs and focuses on dropping his cigarette and stamping it out.

"Apparently you've forgotten what our progenitor looked like. Allow me to refresh your memory." He turns to face his younger brother, settling his expression into the too-familiar lines of their father's scowl.

"Nothing like."

"If you're going to lie, make it believable." Mycroft is starting to get impatient with Sherlock's stubbornness. Sentiment is not a forte for either of them. "The secret to a lie is -"

"That you wrap it in a truth," Sherlock finishes. "You couldn't pass as Father to anyone but a blind person."

"And apparently our mother," Mycroft says before he can stop himself. "She would know, she lived with him for 26 years."

"She's wrong."

Mycroft doesn't reply. Sherlock takes a long drag on his cigarette and blows a smoke ring. They watch a family pile out of a car with green and gold balloons.

"Birthday," Mycroft says almost instinctively.

"Grandfather, by the color scheme," Sherlock replies.

"77? Not a banner year, at any rate, but old enough to have grandchildren that size," Mycroft continues.

Silence again. The children race by them, nearly losing the balloons to the automatic door closing on the strings. The parents come at a slower pace, faces set in enduring cheerfulness. Mycroft recognizes the expression.

"Sherlock," he begins, not quite sure where he wants to go with the sentence.

"You should go back in. You were always the good boy, she'll expect you to come back."

"Not if she sees me as Siger instead."

Sherlock smirks. "With that nose? Please."

He stamps out his cigarette and walks away. Mycroft stares after him, pondering. Deciding.

He'll try again. And try not to wish too hard for the day she forgets her husband as well as her son.