Taking to Instagram, the Hollywood star shared a series of pictures of Emma, including one of her with her two young daughters Mabel and Evelyn, and wrote a lengthy message about their close bond.
Demi wrote: "@emmahemingwillis: I #SeeHer as family who I am honored to call a friend. Our children are sisters and yet there is no name for what our family connection is to one another.
VIDEO: Bruce Willis and Emma Heming's daughter learns how to ride a bike
"We are mothers united, sisters bonded on this crazy adventure of life. Emma is a beautiful mother dedicated to her family, an absolutely gorgeous woman and now she can add business entrepreneur to her resume.
"She carved a path quietly on her own to create @cocobabaofficial, launching the first body skincare products for woman to mother themselves! We all need that!
"Her drive, determination and passion is uplifting and the woman that she is absolutely inspiring."
Demi Moore paid a sweet tribute to Bruce Willis' wife Emma Heming on IWD
Emma was clearly touched by the message, and responded: "Well if this didn't touch my soul. Thank you Demi. I adore you too."
The star's famous friends also commented on the post, with Helena Christensen writing: "Beautiful tribute from a wonderful spirit," while her daughter Rumer Willis added: "This is so beautiful."
The Ghost star, 58, shares daughters Rumer, 32, Scout, 29, and Tallulah, 26, with Bruce, and spends a lot of time with Bruce, Emma and their two little girls.
Demi's heartfelt tribute to Emma
At the beginning of the pandemic in 2020, the Die Hard actor even spent weeks isolating with his ex-wife and daughters in Idaho. Emma, Mabel and Evelyn were due to join the actor, but ended up getting stranded in Los Angeles due to the travel restrictions.
Scout opened up about the situation during a recent episode of the Dopey self-help podcast. She said: "My stepmom was going to come up here too with my little sisters…
Demi and Bruce have remained close friends following their divorce
"My dad came up here early and then travel got crazy and my stepmom stayed in LA."
Bruce reunited with Emma and his youngest two daughters at the beginning of May, just in time for Evelyn's birthday.
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