‘3rd Rock from the Sun’ star Kristen Johnston says her younger sister has died following ‘battle with addiction’

Kristen Johnston is mourning the loss of her younger sister.

The “3rd Rock from the Sun” star said her sibling, Julie, “lost her battle with addiction” on Monday.

“I know she’s finally at peace,” Johnston, 52, tweeted Tuesday morning. “She had the best belly laugh in the world.”

Johnston included a photo showing her and Julie smiling next to each other.

Johnston starred as Sally Solomon on 1990s sitcom “3rd Rock From the Sun” and won two Emmy awards for her performance. She currently plays Tammy on the comedy series “Mom.”

The actress has been open about her own struggle with addiction, including speaking about her past use of drugs and alcohol in her 2012 memoir “Guts: The Endless Follies and Tiny Triumphs of a Giant Disaster.”

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