Chicago Fire Star Dermot Mulroney & His Ex-Wife Had Quite The Age Gap

Hollywood has no lack of age gap relationships to talk about, even after one ended in January 2026. In June 2025, "Chicago Fire" star Dermot Mulroney filed for divorce from his long-term partner Prima Apollinaare, who is 10 years younger than him. The pair first started dating in 2008 and had their first child together that same year, despite it only being a year after Mulroney's first divorce. They then had a second daughter together shortly before their wedding in December 2010. "A lot of it doesn't make sense, but you can't deny your heart," Mulroney admitted on "The Rosie Show" in 2012 when addressing the couple's rushed timeline.

After almost 15 years together, Mulroney and Apollinaare called it quits over unspecified differences that drew the couple apart. They chose to settle their divorce outside of court on January 16, 2026. "No one is asking for anything, and no one is denying anything," an insider told People at the time of filing. "They are not arguing over the children nor money. They used mediators, not lawyers, as they are friends and this is amicable. They were advised to file this way." 

Mulroney was previously married to actor Catherine Keener, who is nearly 5 years older than him, and the pair share son Clyde Keener Mulroney. The stars were married even longer than Mulroney and Apollinaare, wedding in 1990 and finalizing their divorce in 2007. The real reason Dermot Mulroney and Catherine Keener got divorced after 17 years of marriage was similar to the downfall of his marriage to Apollinaare. "There are irreconcilable differences between the parties that have led to the irredeemable breakdown of the marriage," read the court document Extra obtained at the time.

With everyone wanting a peek inside the love lives of "Chicago Fire's" hottest stars, Dermot Mulroney and Prima Apollinaare's age-gap marriage was not a secret to fans. Not only was Mulroney constantly in the public eye for his storied acting career, but Apollinaare became a solo musician in 2017 with her debut single, "Stand Up for Love." What reportedly brought the now-exes together in the first place is a mutual appreciation for music. They share two daughters together, Mabel Ray and Sally June. When they filed for divorce, Mulroney requested spousal support as well as legal and physical custody of their two daughters. 

Like the time Mulroney really walked off "The View" during a writer's strike, the divorce was met with criticism. Many were surprised by his request for spousal support from Apollinaare. "He wants spousal support? What the hell does she do for a living? Never heard of her," a Redditor asked on a thread discussing the divorce update. Other online users brought up his previous divorce from Catherine Keener. The similar length and nature of his two marriages to women in the entertainment industry makes it easy for others to draw comparisons. "I didn't even know he was divorced from Catherine Keener!" a Facebook user commented on NBC News' post about Mulroney's second divorce. "This guy gets divorced more than he changes his underwear," an Instagram user commented on TMZ's January 2026 post (it's important to note that he's only gotten divorced twice). Just like many Hollywood age-gap relationships, Mulroney and Apollinaare's marriage did not stand the test of time.