The Woman Who Dived Into the Heart of the World — Sabina Berman

In the wake of her sister's death, Isabelle moves from her home in California to her birthplace in Mexico to take over the running of the family tuna company. There, she discovers a wild child with no name, who turns out to be the autistic niece she never knew she had. Isabelle names the girl Karen. So begins a miraculous journey for Karen.