The Young Necromancer's Guide to Ghosts

Nebula Award winning fantasy novel Lusi can see ghosts. And that's only the beginning of her problems. Lusi is a perfectly normal 12-year-old wizard except for the part where she can talk to ghosts. But everyone knows ghosts aren't real, so at best they think Lusi is lying and at worst that she's lost her mind. Her big sister Marsi is the only one who believes her, but Marsi is running away to escape Uncle's terrible plan to make her marry his creepy nephew.
Lusi can't imagine being separated from her sister and leaves behind the rest of their family to flee with Marsi via merchant caravan to the Wizards Guild for help. All their plans are dashed to pieces when Uncle catches up to them in a matter of days. Uncle's connections to powerful wizards make him far more dangerous than Lusi initially realized. But Lusi isn't crazy or a freak for talking to ghosts: she's a necromancer! Marsi is worried-they've always been told that necromancers are monsters.
Lusi needs to learn more to set both their minds at ease. She must enlist the help of a ghost girl, a dragon, and a strange wizard from the other side of the world if she wants to control her unusual talents and keep her family safe.