We have a female who gave birth 4 or 5 days ago, and when we went to clean cages last night we discovered one of her babies had gotten under a piece of "box" she had in there to make a house out of, but had chewed all up. Apparantly she had laid on top of it or something strange because the baby was squashed flat dead under the piece. Does anybody else who provides "houses" have issues with that or do I just need something besides cardboard that she can chew up?