There was this book from my childhood- it took place on a tropical island, maybe Hawaii or the Caribbean. There was a healer woman in it, but people had stopped going to her fo remedies because they had a new, modern doctor, and I know her first name/nickname and part of the book title was Dona. (The reason I know it was Dona or something similar is because my brother used to say "Donut" instead)
In the book, a boy got stung by a scorpion and began to die, and the doctor couldn't get medicine for him quickly enough, so Dona stepped up and saved him with natural remedies, and she was celebrated. Last pages reveal she was also the narrator of the story.
The art was very pretty and detailed, and it looked hand drawn.
It was in my grandma's house, I know it was paperback and not too long.
Anybody know?