I have a two year old son who loves to look at his books. We had an issue with him while he was teething. He always wanted to take a book to bed with him. Well we found out that he had been using the books not only for the pictures - but for teethers! Most of the books have no book binding left. My wife and I joked about how he was getting his fiber. We had to replace some the books because the stories were our favorite. I would routinely find huge chunks of paper and glue in his bed. I know he must have swallowed some!