Ben Affleck & Ana de Armas Enjoy Outing with His Kids as Source Says They're 'Very Happy Together'

Karen Mizoguchi

Ben Affleck and Ana de Armas took their romance to the next level as she was seen out with his three children.

On Saturday, the couple, who met on the set of their upcoming movie Deep Water, were spotted taking a stroll in Los Angeles with his kids: daughters Violet, 14 and Seraphina, 11, as well as 8-year-old son Sam.

The group all wore face masks as eldest child Violet was seen leading their family dog Birdie, who is owned by Affleck's ex-wife Jennifer Garner.

"They are very happy together," a source tells PEOPLE of Affleck, 47, and de Armas, 32, who made their relationship public in March.

While the outing on Saturday marked the first time de Armas was pictured with all of his kids, the source says Affleck "continues to work on co-parenting" with Garner, whom he split from in 2015 and finalized their divorce in October 2018.

"Ben and Jen work together at that," the source adds of the exes who are sharing custody of their children.

RELATED: Ana de Armas and Boyfriend Ben Affleck Share the Same Shirt While Social Distancing Together

Affleck has previously spoken highly of his ex-wife's parenting, telling PEOPLE in February that they have always made it a point to be united for their kids.

"When you have children with somebody you're connected to them forever," the actor said. "And I’m very lucky she is the mother of my children."

Affleck added, "I'm very grateful and respectful of her. Our marriage didn’t work, and that’s difficult. Both of us really believe that it’s important for kids to see their parents respect one another and get along, whether they’re together or not."

RELATED: Ben Affleck and Ana de Armas: Everything We Know About the Couple Who Had an 'Instant Connection'

These days, the father of three has been staying at home with girlfriend de Armas, and they have been seen on almost daily walks around his neighborhood in Los Angeles.

"They seem to have a great time together," a source previously told PEOPLE. "They order delivery food and groceries and only leave the house for walks around the neighborhood with their dogs. Ben looks incredibly happy. They are flirty and goofy. Ana always has a huge smile around him."