Mycroft was dog tired. It had been a taxing day at his school and all he wanted was to collapse into his bed, bury himself under a blanket and pretend to be a rock until the late morning.

He peeled off his clothes and threw himself, still wearing his school slacks, into bed.

Only, he found it already occupied.

"Sherlock..."

The child's reply was formal in the extreme, "Mycroft."

Mycroft's head found a pillow and he rolled under his covers like his brother was not even there.

"I know I'm going to regret asking this…" and lord how he would, "But what are you doing in my bed? Surely you haven't gotten lost?"

Sherlock said nothing and did nothing. He steadfastly refused to budge an inch, even with Mycroft nudging him gently out of the middle of his bed.

Mycroft rolled his eyes and tried another tactic.

"Mummy will be most displeased to find you sleeping in someone else's bed. It's not a very grown-up thing to do."

But Sherlock did not take the bait. Mycroft's bed was where he was staying and nothing anyone could do was going to change that.

"If this is that darn cat again…!" Mycroft let the threat fall away, but Sherlock knew that it was there, lingering between them.

His fingers unconsciously became curled around Mycroft's pajamas. He gripped ahold of them as though he'd never let go.

"It is that cat again, isn't it?" Mycroft hadn't meant for his words to sound so accusing. Or to have such a bite.

Sherlock flinched, as though he'd been struck.

"Sherlock, really now. This has gone far enough. I'm very tired—"

"Then sleep." The command was low. It was very nearly begging.

For a moment he considered picking Sherlock up, carrying him to his room and sitting against the door until the impudent child gave up and faced his fear. He could sit there and let himself be lulled to sleep by the sound of his baby brother's pleading cries and the cat's shrill hisses.

But he was too tired. He wrapped his arm around his brother and pulled him closer to his chest, like a large teddy bear. He rested his head atop the ebony curls and waited patiently until his brother's breathing had evened and slowed.

Then, sometime after that, he drifted too.