`` Bonanza '' star 's son Mark Landon found dead in West Hollywood home . He is best known for his 14 years as `` Little Joe '' Cartwright in TV 's long-running `` Bonanza , '' and later as Charles Ingalls in nine seasons of `` Little House on the Prairie . '' By Michael Martinez and John Antczak, NBC News LOS ANGELES -- Mark Landon had a few acting credits , playing small roles in three movies .
`` Bonanza '' star 's son Mark Landon found dead in West Hollywood home . By Michael Martinez and John Antczak, NBC News LOS ANGELES -- Mark Landon had a few acting credits , playing small roles in three movies .