Nook HD+ is sturdy
With the current very low prices, get a Nook HD+. You can set up a separate child account to allow only the books and apps you wish the child to use, and still get plenty of use from the tablet yourself. My 3 year old grandson started reading/playing with my Nook Color when he was only 2, and now has access to my Color and HD+, and his mother's Nook tablet and HD+. He is not allowed to have them with him at nap or bedtime--he gets a cuddle and real book read to him then. While there are few formal restrictions on the length of time he can use them, he has no problem setting them aside to interact with other people, toys, or pets. The devices are in sturdy covers ,and have not broken yet. Paper books are wonderful, and he loves them; e-books can be interacted with in way paper books cannot.