June Lockhart, Beloved TV Mom, dies at 100

June Lockhart, beloved for her roles as a mother in Lassie and in Lost in Space, died on Oct. 23 at her Santa Monica, California home of natural causes. She was 100.

Harlon Ball, Lockhart’s spokesman, confirmed her death to The New York Times.

Lockhart made an indelible mark playing Ruth Martin, the foster mother of John Provost’s character, Timmy, and his collie Lassie, on the series lassie beginning in 1958. She took over the role from Cloris Leachman in the show’s fifth season, and she remained on the show through 1964.

She went on to star as Dr.Maureen Robinson – a biochemist, wife, and mother – in the sci-fi adventure television series, Lost in Space. She appeared in all three seasons of the show, from 1965 to 1968.