Patrick Duffy (born March 17, 1949) is an American actor and director widely known for his role on the CBS primetime soap opera Dallas, where he played Bobby Ewing, the youngest son of Miss Ellie, and the nicest brother of J.R. Ewing (played by Barbara Bel Geddes and Larry Hagman respectively) from 1978 to 1985 and from 1986 to 1991. Duffy returned to reprise his role as Bobby in a continuation of Dallas, which aired on TNT from 2012 to 2014. He is also well known for his role on the ABC sitcom Step by Step as Frank Lambert from 1991 to 1998, and for his role as Stephen Logan on the CBS daytime soap opera The Bold and the Beautiful (2006–2011, 2023-present). Duffy played the lead character's father in the 2014 NBC sitcom Welcome to Sweden.