"The tree says that the other daughter mentioned in familysearch's summary of Richard's obituary, Lisa Lee Gowell, is a half sister born 11 July 1949 in Tampa, Florida, so presumably the daughter of Richard's second wife Elaine Margaret Childs, who died 26 June 2006 in Seattle. Lisa is said to have died in 2002 in St Bernard's Parish, Louisiana."
Okay, we're making some headway. The Richard Gowell born in Swampscott is the one I'm after. This confirms what I suspected, that his first wife was Geraldine and they were the parents of Karen [who died in 1998 in Santa Clara County, California]. Richard's second wife was Elaine Childs [she's the one who is related to me].
In 1950, Elaine was living in Massachusetts with her great aunt and uncle [my grandparents]. She was still single and she did not have a child. So, Elaine was not the biological mother of the daughter, Lisa, born in 1949. Perhaps Lisa was adopted. One of Elaine's obituaries mentions that there were four adopted children.
http://www.rootschat.com/links/01sui/Richard and Elaine were married in about 1952 but I have not found the exact date or place. The best possibilities are Connecticut or New Orleans. In addition to Karen and Lisa, they had a son named Timothy Oliver Gowell, born 1965 in New Orleans. For some reason, he later changed his name to Steven James Gowell. He died in King County, Washington in 2013. Given his birth date, I suspect that he was actually the son of Karen, but that's just a hunch. If the obituary is correct, there were some other adopted children and I think I know their names, but they are probably still living so we'll leave them out of this.