Hi! I recently got two adorable ratties and already had to treat them for lice they got from their bedding. I want to build them a playpen and jungle gym out of cardboard boxes, but I'm kinda terrified of having to deal with the lice again. Will they be OK with the cardboard boxes or should I sanitize them or do I not need to worry about it with those types of things? Is there even a way to sanitize cardboard? Some kind of list of what I should freeze or whatever I have to do before giving to them? I feel so completely clueless right now, please help!!!