Hilary Duff and her ex, Mike Comrie, put on a united front over the weekend to celebrate their son's third birthday.
The singer/actress ' sister, Haylie Duff, posted photos on Instagram from the bash.
On Saturday, the aunt – who is a mom-to-be herself – could be seen munching on cupcakes with Hilary.
Haylie Duff posted this photo eating cupcakes with sister Hilary Duff at Luca’s third birthday party on March 21, 2015 (Instagram)
"Going hard for Luca's 3rd birthday. @hilaryduff," she captioned the pic.
In another photo, Mike posed with Haylie's fiance, Matt Rosenberg, while carrying the little boy's Lightning McQueen cake that was comprised of dozens of cupcakes.
Haylie Duff posted this photo of fiance Matt Rosenberg and former brother-in-law Mike Comrie carrying her nephew Luca’s third birthday cake on March 21, 2015 (Instagram)
"Haylie March 21 Cutest Dad-to-be & Dad around! @mattyrose3 & Mikey," Haylie captioned the second snapshot.
Hilary also honored Luca's March 20 birthday on Instagram, sharing a slideshow of her adorable son through the years.
"3 years buddy! 3 beautiful years! You make every minute worth while! We cherish all your firsts and all that is to come Happy 3rd birthday my love #timesflying #whatayear," the mom captioned the video.
Hilary gave birth to Luca on March 20, 2012. She and Mike separated in January 2013 and she officially filed for divorce on February 20, 2015 after over four years of marriage.
-- Paige Feigenbaum