"The Twits" was a favorite of my younger kids. I recently read "The Lion, The Witch, and the Wardrobe" to them, and they loved it. Of course we had to make Turkish Delight after learning about it in the book. Other winners include: Redwall series, The Wingfeather Saga, Artemis Foul series, The Phantom Toll Booth. But 4 is a bit young for those.
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