I'm fixing up my old dollhouse from when I was a kid. I am NOT an expert at dollhouses ;) My problem is many of the windows are yellow now. About half of the windows are in the house and half have not been put in yet. Is there anything I can do other than taking out the windows and redoing it all? What material do you suggest using that won't yellow? I would put glass in them but don't want to risk it breaking if a kid is using the house.. and I don't see how it would work anyways since it is way thicker. Many of these windows slide open. Thanks for any help.