How to remove a washed on dried on sticker from clothes?

My son put a sticker on his PJ's and it went through the washer/dryer like that. The top part of the sticker came off in the wash but now there is the sticky stuff and white paper stuck to his pj's that I cannot get off. Of course this is his favorite set of pj's and he is just heart broken. I am hoping that someone can tell me a way to get this off his pj's without ruining it.