Jennifer Lopez and Ben Affleck ‘Still Moving Forward’ in Divorce Despite Friendly Lunch Together (Exclusive Source)

Jennifer Lopez and Ben Affleck are not romantically reconciling.

Despite having a friendly lunch with their kids over the weekend, “They are still moving forward with the divorce” and “working out financial details amicably,” a source tells PEOPLE.

“They all came together for a fun lunch so the kids could hang out,” the source adds of their gathering, which included Affleck’s two younger children Seraphina, 15, and Samuel, 12, plus Lopez’s 16-year-old twins Max and Emme.

The source says the group dined at the Polo Lounge inside the Beverly Hills Hotel in Los Angeles on Saturday, Sept. 14, less than a month after Lopez, 55, filed for divorce from Affleck, 52.

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Affleck’s 18-year-old daughter Violet, who recently left for college at Yale University in New Haven, Connecticut, was not in attendance at the lunch, but spent time in New York’s the Hamptons over the summer with Lopez.

Despite spending the summer on opposite coasts, Lopez and Affleck also came together multiple times to celebrate his kids in the months ahead of Lopez’s Aug. 20 divorce filing, including for Violet and Samuel’s graduations.

The source tells PEOPLE that “a divorce is never easy,” and “the kids always got along and have fun together. It makes [Lopez] happy seeing the kids happy together. Happy kids are her priority.”

Lopez recently returned from a trip to the Toronto International Film Festival, where she made her first public appearance since her divorce filing at the premiere of Unstoppable on Sept. 6.

A source told PEOPLE at the time that the actress and singer “was happy to be in the spotlight again because of work.”

“She’s so over all the attention on her personal life,” that source added. “The film festival truly uplifted her. She was excited to focus on work again.”

While Affleck and his longtime friend and Artists Equity production company co-founder Matt Damon also served as producers on the true-story sports drama, Affleck did not attend the premiere.