Theodosia and the Serpents of Chaos by R. L. LaFevers

Theodosia Throckmorton is an 11-year-old girl living in London in 1906. She sleeps in a sarcophagus, and can read hieroglyphics. In short, she's not your average girl. Theo's parents run London's Museum of Legends and Antiquities, the place where she spends most of her time. What her parents don't realize is that many of the antiquities that Theo's mother brings home from her archaeological expeditions are cursed. It's up to Theo to remove the curses, unraveling international intrigue along the way.