Joan Templeman, the wife of billionaire businessman Sir Richard Branson, has died at 80, her husband announced.

Branson, the founder of Virgin Group, and Templeman married in 1989 and remained together until the latter's recent death.

"She was the most wonderful mum and grandmum our kids and grandkids could have ever wished for," Branson shared in an Instagram tribute to his late wife. "She was my best friend, my rock, my guiding light, my world."

While we don't know a cause of death just yet, we'll keep you updated once we know more about this very sad update concerning Templeman's passing.

What terrible, terrible news for the Branson family.

This article originally appeared on For The Win: Joan Templeman cause of death: What we know on Richard Branson's late wife

Reporting by Cory Woodroof, For The Win / For The Win

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