In the last of the episodes dealing with the mothers of Adam, Hoss, and Little Joe, Ben Cartwright while on a trip to New Orleans meets up with Felicia Farr, widow of a man who was working on the Ponderosa and saved his life. With his dying breath he asked Lorne Greene to look up his mother and estranged wife in New Orleans.
He looks up mother Lilly Valenty a proud and haughty French aristocrat and then the widow who has something of a reputation. It's in defending that reputation that he's forced to do a number on another New Orleans aristocrat, George Dolenz.
Unlike the story of Adam's mother whose story was told in one episode and Hoss's mother who had a two part episode stretched out over a different season, this story ends with Lorne Greene and Felicia Farr promising marriage with him promising to take her back to the Ponderosa. In the episode it is mentioned how she died, but Felicia Farr never came back to film a second episode. Little Joe was born and it is mentioned how his mother died as the story is told in flashback like the other two.
There is mentioned however something that did provide the basis for another future Bonanza episode, but I won't reveal.