What were the given names of the three sisters on the TV show 'Petticoat Junction'?

Set in the rural town of Hooterville, the show followed the goings-on at the Shady Rest Hotel, of which Kate Bradley (Bea Benaderet) was the proprietor. Her lazy Uncle Joe Carson (Edgar Buchanan) helped her in the day-to-day running of the business, while she served as a mediator in the various minor crises that befell her three daughters: Betty Jo, Bobbie Jo, and Billie Jo. The actresses portraying Billie Jo and Bobbie Jo changed over the years. Billie Jo was played by Jeannine Riley the first two seasons, and then by Gunilla Hutton for one year before Meredith MacRae assumed the role for the show's remaining seasons. Pat Woodell was the original Bobbie Jo for two years, with Lori Saunders playing the part subsequently.

Betty Jo was portrayed by Linda Kaye (Henning), daughter of series creator Paul Henning, for the entire run.

More:

https://en.wikipedia.org/wiki/Petticoat_Junction