The night before the trial, Sherlock climbed down off the other bed in the middle of the night and crawled in next to him. Mycroft inhaled his little brother's smell, somewhere between peach shampoo and sulphur, and sighed, wrapping one arm around him.
"Croft, I'm frightened." He whispered.
"I don't want to go with Daddy tomorrow." Sherlock's body quivered involuntarily, and Mycroft pulled him closer.
"Me neither. No one will let it happen."
"I don't want you to be scared again. I don't want you to get hurt anymore." Sherlock looked up at his brother, imploring him with his eyes.
"We won't have to go with him. I'll make sure of it." Mycroft tried to sound brave.
"What if you fail? What if we have to go back?"
"Trust me, we won't go back. Whatever it takes, I'll make sure we don't go back."
"What do you mean?"
"I mean... I mean that he will never, ever touch us again. I would rather die."
"I don't want to die!" Sherlock pushed away from Mycroft.
"It's okay. I promise it will be okay." It was all he could offer without revealing the backup plan. He didn't want Sherlock to know about the backup plan. If he had to execute it, the whole thing would be quick and painless for the little boy.
"Croft, I'm afraid."
"You wouldn't hurt me, would you?" Sherlock looked away. Mycroft's eyes widened.
"How could I ever hurt you?"
"To stop Daddy." He said slowly, his eyes never rising to meet his brother's, his voice little more than a croaky whisper. He had deduced the plan a couple of days before, but he had hoped he was wrong. He still hoped.
"It'll be fine. I promise." Mycroft pulled the child closer to his chest and held him, stroking his hair, hushing him whenever he tried to start up conversation, until he fell asleep.