(Set during 2X01)

The soft tapping of Mycroft's umbrella preceded him down the dim corridor of the Mortuary. The muscle under Sherlock's eye twitched as his brother came up to him.

"I know what you're doing," Mycroft said. "It won't work."

"Shut it," Sherlock said, annoyed that his brother knew him quite well.

"As much as you might like to forget, you can't. Not really," Mycroft said.

"Of course I can," Sherlock snapped. The twang of emotion in his voice showed its self as he cut the last word short, and the muscle in his jaw twitched again.

Mycroft's soft sigh was just enough to grate on his nerves. First Christmas, and then this, and now his brother was trying, in his cold, logical way, to be comforting. It was enough to make him want to scream.

But he was Sherlock Holmes, and emotions –real, strong, deep emotions –never escaped his grasp. Anger and irritation didn't count; he was only ever angry or irritated with boring or stupid people.

And Mycroft was just plain wrong; he could and he would.

"It doesn't make things better, Sherlock," Mycroft said.

"How would you know?" Sherlock asked.

"Because I have had to live with memories, just like you." Mycroft gave him a knowing look. "Go into your mind palace if you like, delete all of your knowledge that deals with Irene Adler, you still can't delete memories. The human brain doesn't work like that."

"You're wrong. And there are precious few memories of Irene Adler for me to delete," Sherlock said, closing his eyes.

Mycroft's voice still wormed his way into his ears anyway. "I'm sure you had a lot more of Vesper."

Sherlock turned away.

"You can't forget her, Sherlock," Mycroft said. "Don't try."

"Why?" Sherlock asked, his voice barely a whisper.

"It's Christmas," Mycroft said. "She loved Christmas."

"Oh, so you expect me to –to just get into the spirit for her, or cry, or say something moving, or–" Sherlock's tone took on deep derision and became scathing.

"No, I'm not," Mycroft said. "We're not like that."

All the irritation with Mycroft drained away from him and left him hollow and empty, like a husk. Sherlock took a deep breath, staring out the window. "Do you ever wonder," he said at long last, "if there's something wrong with us?"

Mycroft shook his head, reaching into his pocket and pulling out a lone cigarette. "All lives end. All hearts are broken. Caring is not an advantage, Sherlock," he said quietly. "But remembering is something else entirely."

Sherlock took it from him, and as he lit it and inhaled, he frowned. "This is low tar."

"Well," Mycroft said. "You barely knew her."

And then his umbrella went softly tap-tap-tapping away.

You couldn't often see the stars in London's sky. Too many lights, too much smoke, buildings so tall that the blocked the sky… but tonight, Sherlock could see them.

Against his will, his mind began to identify and catalogue what he saw. Orion, Polaris… while stars looked like tiny pinpricks of light, they were really great balls of luminous plasma held together by gravity…

He shivered and forced his mind away. He had deleted that. He had thrown it out. He didn't need to remember it…

Who was he kidding? Vesper's telescope was still in a box under his bed. Whatever he might try to delete in his head, however clean he kept his mind, he was more of a pack rat in his physical life. It seemed that even though he did not wish to remember, he was afraid to forget.

Vesper. Evening Star.

His little sister had loved astronomy.

She was the most human of the three of them. All the Holmeses were known to be cold and rather calculating, but when they were passionate about something, they really came alive, and it was the most obvious with Vesper. She would always make him drive her out to the country to go stargazing, and he would always moan and groan about it. But while she would stare at the stars, he would stare at her, and watch her face light up, and wonder how she did it –how she let her emotions be so…free.

He didn't talk much to anyone after he left home, and months would go by before he remembered that his family might like to know how he was. Mycroft was into the British government pretty well by then and managed to keep tabs on him, letting the family know how he was. He saw no need to make a redundant report of his own.

So, he hadn't seen her for a long, long time when they got the news and told him of the cancer.

He was set up on his own as a private consulting detective by then, the only one of his kind. He could solve any crime; unravel any mystery.

What could he do against a disease?

He got very, very good at chemistry, biology (not that he wasn't already) but in his spare time he would go over to the hospital and harass the doctors and nurses into giving him her charts and test results, and he'd make his own conclusions.

It seemed the truth had been staring him in the face for ages, but for the first time in his life he had refused to see it.

She died a week before Christmas.

She didn't have a will, really, but she had written some letters to each of her family members, and in his, she had mentioned those trips, and had given him the telescope.

Handwriting told him lots about people –hers was logical and controlled, like all Holmeses hands, but there was a little fanciful loop here and there on her y's and her l's. There was a dreamer in her, hidden away.

And it would never come out again.

So he had deleted it. Deleted it even to the point of forgetting that the earth went around the sun. Told himself it was rubbish, that he didn't need it anyway, that he'd make room for the really important stuff.

But he couldn't forget the memories. He couldn't forget Vesper.

Caring –emotion, debilitating caring –was not an advantage. It broke down minds and incapacitated people into quivering balls of jelly.

But Mycroft was right. Remembering was something else entirely.

AN: My lovely, lovely friend told me her headcanon for the reason why Sherlock deleted all of his astronomy knowledge, and she very graciously allowed me to write a fic about it. So this is for her. :)

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