June Lockhart Dies at 100: ‘Lost in Space’ Costar Bill Mumy Reflects on the TV Icon (Exclusive)

Barb Oates October 25, 6:20 pm

June Lockhart, Bill Mummy, Everett Collection, Lost in Space — Everett Collection

On October 25, 2025, June Lockhart, star of Lassie, Lost in Space, Petticoat Junction, and so much more, passed away at the age of 100 from natural causes. In June 2025, just weeks before her 100th birthday, ReMIND spoke with Bill Mumy, her Lost in Space costar, to discuss his memories of the beloved actress, who had been a staple of the big and small screen since Hollywood’s Golden Age. Lockhart thrilled generations of fans, with a career that lasted for almost 90 years. For so many Americans, she felt like part of the family, the mother we never had

In honor of her memory, we’re re-sharing our June 2025 interview with Mumy, where he reflected on his on-set memories of Lockhart, and their relationship that remained decades after the Robinson family left TV.

Our June 2025 interview with Bill Mumy about June Lockhart

Most know that Lockhart and Mumy starred in TV’s sci-fi classic Lost in Space (1965-68), which followed the Robinson family as they set out to find an alternate planet to inhabit as Earth’s overpopulation was nearing a crisis. Lockhart played the family’s matriarch and biochemist Maureen Robinson opposite Guy Williams‘ patriarch, Dr. John Robinson. At the time, she had traded in that gingham gown she donned for six seasons of Lassie for the cooler, form-fitting sparkly jumpsuit for Lost in Space.

LOST IN SPACE, in front, from left: Mark Goddard, June Lockhart, Billy Mumy, Angela Cartwright, Jonathan Harris, Marta Kristen; in back: Guy Williams, 1965-1968. ph: TM and Copyright ©20th Century Fox Film Corp. All rights reserved. /TV Guide / Courtesy Everett Collection

Mumy starred as the infamously nerdy Will Robinson (“Danger, Will Robinson! Danger!’), the youngest of the Robinson clan, which also included Judy Robinson (Marta Kristen) and Penny Robinson (Angela Cartwright).

Mumy gave us some behind-the-scenes information on what cast members would do to celebrate birthdays on set back in the 1960s.

“Well, Angela and our birthdays were always celebrated on set with cakes and stuff because we were kids,” Mumy shares. “The rest of us, we knew people’s birthdays and throughout all of the decades sent birthday cards and calls and things like that. It’s always been and continues to be a real kind of unconventional family. Everybody got along really well.”

LOST IN SPACE, Sci-Fi Channel commemorates the 'launch date' of the Jupiter II with a LOST IN SPACE marathon, from left: Jonathan Harris, Bob May, Dick Tufeld (voice of 'Robot'), Angela Cartwright, Bill Mumy, Mark Goddard, Marta Kristen, June Lockhart, aired 10/16/1997.

1997 ‘Lost in Space’ reunion © Sci-Fi Channel/ Courtesy Everett Collection

In June 2025, we asked Mumy if he still was in contact with Lockhart.

“I talk to her through her daughter. June is at home. She has two assistants. She’s still in her own home. She follows the politics, she reads the news, but she doesn’t talk on the phone and she doesn’t — obviously — she’s not going to put on all her makeup and go out and do a convention or anything anymore, but she’s, well, she’s fine.”