Winthrop's toenails have been getting long, and while I've been trying to gradually work on them with an emery board-- I don't want to use sand perches because they can cause bumblefoot-- they're getting in the way of his walking (the front tips of his toes lift up). That said, he does mainly walk on his toes-- the arch of his foot is above the ground usually. Is this normal? Also, he crosses his toes, or more accurately, his toenails. Is this something to worry about?