The actress also poses with Joel Madden's wife, Nicole Richie.
Hilary Duff is taking the idea of amicable exes to the next level. The 36-year-old How I Met Your Father star showed her support for her ex, Joel Madden, and his band, Good Charlotte, with her husband, Matthew Koma, even joining the group for a live performance.
Koma took to Instagram on Monday to post a series of videos and photos from the performance, which took place at the When We Were Young Festival in Las Vegas.
"Played in my buddies’ band @goodcharlotteband this weekend, drank Jared Leto’s coconut water, & played A Milli with Lil Wayne, 10/10," Koma captioned the pics.
Joel, who dated Duff from 2004 to 2006, commented on the post, "You are the heart and soul of GC 😍," while his twin brother, Benji Madden, added, "We decided we Really can’t play with out you now 😭😭😭❤️❤️❤️❤️."
For her part, Duff was right in the action supporting Koma and her ex from backstage.
Duff also posed with Madden's wife, Nicole Richie, at the show, for a smiling selfie.
This isn't the first time the couples have shown that they're friendly.
Back in March, Koma posted a series of pics with Madden for the rocker's birthday. In one trolling shot, he posted a throwback photo of Duff and Madden from when they were a couple, writing, "It's not even that weird that you dated my wife @joelmadden it just makes me feel closer to you."
Duff and Madden started dating in 2004 when she was 16 and he was 25. They split in 2006 and one month later Madden began dating his future wife, Richie.
In a 2015 interview with Cosmopolitan magazine, Duff implied that she lost her virginity to Madden.
“I had a 26-year-old boyfriend,” Duff said when asked about when she lost her virginity. “So everyone can make their own assumptions about what I was doing.”
Even further than being friends, Duff revealed in a January appearance on Watch What Happens Live With Andy Cohen that they're also neighbors.
"We're neighbors and we actually hang out all the time," she shared. "I was just in [Richie's] driveway honking for her to come drink wine with us the other day."
Duff is mom to son Luca, 11, with ex-husband Mike Comrie, and shares daughters Banks, almost 5, and Mae, 2, with Koma. Joel and Richie share daughter Harlow, 15, and son Sparrow, 14.
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