She prefers to sleep on the floor.
Jack was going to visit his two favorite kids before he had to leave for spring. He went to Jamie's window because he knew it would be open as Sophie sometimes forgets to unlock hers after her mom closes it.
Jack pushed the glass open and saw Jamie sitting on his bed reading a book. It must have been a good one because he didn't even look up when Jack stepped in and started to look around. He was about to start to walking around the room when Jamie finally saw him.
"Hey Jack." He whispered, a large smile growing on his lips.
"Hey kiddo." Jack said just as softly. "Why are we whispering?"
"Because Sophie's sleeping." Jamie told him.
A look of confusion crossed Jack's face. "Isn't her room down the hall?"
"Yeah, but she likes sleeping here when I'm home." He pointed to the shag rug that was a few feet in front of Jack. On it was the younger girl, curled into a ball, sound asleep in the floor. Jack gave Jamie a questioning look. The boy shrugged.
"She prefers to sleep on the floor."
A/N I think it comes from everyone leaving her on the floor when she was small. Thanks for reading and reviewing!