By Mike Bruno
Updated May 12, 2009 at 01:58 PM EDT

Little House on the Prarie star Michael Landon’s eldest son Mark was found dead in his Los Angeles home on Monday, the AP reports. His age was reported as 60. The cause of death was not immediately clear, but police say there is no evidence of foul play. Mark Landon appeared in three movies, including Us, a CBS television movie written and directed by his father in 1991 just before he died of cancer at age 54, as well as the TV shows Bonanza and Highway to Heaven.