I did Lassie for six years and I never had anybody come up to me and say, 'It made me want to be a farmer.'

Lockhart appeared as Dr. Lockhart starred as James Caan's mother in an episode of Las Vegas in 2004. In February 2013 Lockart began filming for Project Fedora (working title) a video game that combines live-action footage with 3D graphics.

She is remembered as the mother in two TV series Lassie and Lost in Space. Janet Craig on the CBS television sitcom Petticoat Junction (1968–70).