Madden and his wife, Nicole Richie, are neighbors with Duff and Koma.
It's safe to say that Hilary Duff's husband, Matthew Koma, and her ex, Joel Madden, are pals. Over the weekend, Koma, 35, wished Madden a happy birthday on his Instagram Stories in a series of cute bro pics and a little fun trolling.
Posting an awkward pic of himself and Madden with their eyes closed, Koma wrote, "Happy birthday @joelmadden."
He also shared a pic of them watching two German Shepherds, writing, "Grateful for you and our friendship @joelmadden."
Koma also posted a pic of a handwritten note, writing, "Matt + Joel 4 Eva," and then took it a step further posting the ultimate throwback pic of Madden and Duff when they were a couple.
"It's not even weird that you dated my wife @joelmadden it just makes me feel closer to you," Koma quipped.
Madden reposted Koma's messages, writing on the pic of him and Duff, "We love you Matt."
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, Nicole 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."
She also quipped about Koma, "Anytime we would hang out, my husband is a giant troll -- it's one of my favorite things about him," sharing that Koma Photoshopped the Madden brothers into a photo with Duff that initially made Madden and Richie think that Duff and Koma didn't like them.
"Now they just know that Matt is a big troll and likes to have lots of fun," Duff said, laughing.
Duff and Koma tied the knot in 2019 and share daughters Banks, 4, and Mae, 1. Madden and Richie married in 2010 and share kids Harlow, 15, and Sparrow, 13.