Q. Rescued a yearling. She had hurt her knee and has layed down in her stall. Should I be worried if she can get up on her own or not?
A. Yes I would try to get her up so at least you know she can manage on her own or not. Please remember with young horses that aren't used to being stalled that if they roll they can cast themselves against the wall. Make sure you check her regularly, especially if she wants to be down. A barn camera is great idea if you can afford one.
Cold hosing does wonders for wounds. Good for you for rescuing her, good luck