It is book #3 in the Grandma Dangerous Series.
WARNING: DO NOT GIVE THIS BOOK TO YOUR OWN GRANDMA. SHE MIGHT GET IDEAS...Danger is her middle name!**Actually, it's MaudeGrandma flies Ollie and Piper in her hot-air balloon for a cursed adventure in Cairo! The third book in the fantastically hilarious Grandma Dangerous series.
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