I can only saw a few parts of this movie but what I saw was this like teenage girl getting grabbed by the arm and swung anf she got swung into the wall and hits her head and she stars bleeding from her mouth I think and the girl that swung her wasn't her mom I think it was someone taking care of her so the lady takes the girl to a summer camp and puts her in a room and won't let her leave and the windows are bared up and she tries bringing her food and the girl pretends to be sleeping but she's in the closet and she tries to get out but I don't think she does then I remember her parents were looking for her and the lady was talking about her daughter drowning at that lake

Please help me

Sounds familiar, but there's a short story about that.
"girl in the basement"