The term 'Happy Days Actress' refers to two actresses who starred in the popular 1970s television show, Happy Days. The first actress is Erin Moran, who played Joanie Cunningham on the show. She had five letters in her last name, Moran. The second actress is Marion Ross, who played Marion Cunningham on the show. She had four letters in her last name, Ross. Both actresses were part of the main cast of the show and were well-known for their roles.