Jennifer Garner and Ben Affleck
Ben Affleck celebrates Christmas Day with Jennifer Garner and their kids. Pictured: Affleck and Garner arrive at the Oscars at Hollywood & Highland Center on Feb. 24, 2013 in Hollywood, California. Getty Images/Jason Merritt

Ben Affleck and Jennifer Garner continue to spend the holidays as a family.

The "Justice League" actor and Garner remain amicable after their split in 2015. Affleck and Garner agreed to prioritize their three children, Violet, 12, Seraphina, 8, and Sam, 5. Thus, they continue to spend the holidays as a family.

An insider told People that Affleck joined Garner and their children on Christmas Day. There are no details as to what the family prepared and shared during their Christmas dinner. However, the "Miracles from Heavens" star shared a revelation on her Instagram Stories that one of their daughters no longer believe in Santa.

Garner shared a snap of cookies, milk and apple with a note "I love you Santa." "I still have two believers," she wrote in the caption.

Although the mom of three did not drop names, many believed that her eldest daughter, Violet, is the one who does not believe with Father Christmas anymore.

Affleck and Garner have also reunited on Thanksgiving. Days before the holiday, the "13 Going 30" star admitted that Affleck and his mom would visit them and take the kids. She added that she wanted to be left in the kitchen to cook for everyone.

"Ben's mom, Chris [Boldt], will be in town and she and Ben will take the kids and I'll have crafts set up and I'll have T-Ball, soccer, I'll have anything set up," Garner told Entertainment Tonight. "If they will play with the kids and just let me cook, it is heaven for me. I will make homemade bread, I'll make stuffing, I'll make a turkey, I'll make gravy, I'll make sweet potato pudding, I'll make pies. Just let me have that day in the kitchen."

Meanwhile, Affleck is still continuing his treatment for alcohol addiction. Earlier this month, he was spotted leaving a residential facility with two women, who were believed to be his coaches. The "Argo" actor has been open about his struggles with alcohol and his desire to be sober.

"This is a lifelong battle, not one that he takes lightly," a source told People about Affleck's alcohol addiction problems. "His focus is on his family and getting better so that he can continue with what he loves."

Earlier this year, Affleck announced on Facebook that he completed an alcohol treatment. According to him, he wanted to be the best dad and show his kids that "there is no shame in getting help when you need it."