Michael Landon ("Little Joe Cartwright" on Bonanza, the father on Little House on the Prairie, and the star of Highway to Heaven), is the adoptive father of Mark Landon (1986's Double Edge) from his first marriage. Mark appeared in the 1991 TV movie Us, which was written, directed by, and starring his father. He was also an extra in 1997's Goodbye America.
Michael's children from his second marriage to Lynn Noe (who was an extra in a 1960 episode of Bonanza) are Jennifer Landon, Michael Landon, Jr., Shawna Landon, and Christopher Landon. Jennifer played "Gwen Norbeck Munson" on As The World Turns from 2005-2010. She made her first onscreen appearance in a 1989 episode of her father's series Highway to Heaven, followed by a role in his TV movie Us.
The younger Michael first appeared onscreen in a 1977 episode of Little House on the Prairie. He also appeared in three Bonanza TV movies and has produced and/or directed a number of TV and film projects, the first of which was a 1991 documentary about his father. In 1993, he wrote the TV movie Bonanza: The Return, followed by 1999's TV movie Michael Landon: The Father I Knew.
Shawna appeared in the 1979 TV movie Little House Years and a 1983 episode of Little House on the Prairie.
Christopher is a producer/writer/director (2007's Disturbia, TV's Dirty Sexy Money, Paranormal Activity 2, Paranormal Activity 3).
Michael's daughter Leslie Landon with his third wife Cindy Landon appeared in 19 episodes of Little House on the Prairie with her father. Her first onscreen role was in a 1982 episode of his show Father Murphy. She also appeared in three Little House on the Prairie TV movies in 1983 and 1984.
Cindy, who co-produced the 2006 documentary Whaledreamers and executive produced the 2011 documentary Staging Hope: Acts of Peace in Northern Uganda, met Michael when she was a makeup artist on the set of Little House on the Prairie. They were married from 1983 until his death in 1991 from cancer.