Odd & True by Cat Winters

Odd & True
A tale of two sisters set in America in the early 1900s. Odette is the eldest, protective of Trudchen, who has polio, but doesn't let that limit her. Raised on her sister's stories about their family being a family of monster hunters, Tru believes those stories.
When Odd leaves on her own adventure, Tru remains with their aunt, who is taking care of them. One day, Odd returns to bring Tru with her on a quest, and Tru learns that some of her sister's tales were altered.
Odd and Tru is a fairy tale about two courageous girls, family secrets, and the Jersey Devil, with fascinating historical details. It's heartbreaking at times, and surprising, and I loved the perfect ending.