Jason Bateman

Jason Bateman started acting at around age ten, and his first television role was at age eleven, as James Cooper, a boy who alongside his sister Cassandra is left orphaned when their parents are killed in an accident. After initially trying to give the children to a relative or have them adopted, Charles and Caroline adopt James and Cassandra themselves. Starting in Season 7 of the series, Jason was featured in over 20 episodes.

Good biography of Jason Bateman from Official Little House on the Prairie website