Lois Gladys Leppard's Mandie series is at least 20 years old. I'd heard of them, but hadn't a chance to read one until the Perma-Bound order someone else made arrived at Blendon. It's a harmless enough historical mystery, (Mandie and the Hidden Treasure was the one I have; book 9) but I don't know that I would have bought it. There is a character named Uncle Ned, and he merits lines like 'The old Indian smiled again. "Must hurry before doctor son get hungry." ' and "Mother of Papoose not like dirt.'
There are also several African American characters who are drawn from the "sho 'nuf" school of dialect: 'You younguns gir in here! Food's on de table, and you keepin' it waitin!'" There is an African American who is a doctor, but given the time period of the book, it seems somehow anachronistic.
Vivian Vande Velde's Smart Dog was a little better-- experimental dog escapes from scientific lab, befriends young girl and doesn't want to go back because he will be dissected; complications ensue. From 1998, this is unlike this author's other works, which tend to be eerie and supernatural, but a fine funny read.