The actress and Martinez, who filed for divorce in October, were photographed driving together on Saturday. A source tells PEOPLE they took Nahla to a party in California's Woodland Hills.
Martinez, who was still wearing his wedding ring, is "very happy that he and Halle are able to keep a good relationship. They want to make the divorce as painless as possible for the kids," the source says.
VIDEO: A Look Back at Halle Berry's Marriage to the Man She Called 'the One,' Olivier Martinez
"They acted friendly and seemed okay," says another source. "They keep spending family time together and seem to get along."
The couple was married for two years, and share son Maceo-Robert, 2. Both cited irreconcilable differences, according to their court paperwork obtained by PEOPLE.
Despite both hiring high-powered Hollywood divorce attorneys, the pair want to proceed without issue and wish to avoid a custody battle, sources previously told PEOPLE.
For more on Berry and Martinez's split, pick up the current issue of PEOPLE
Berry spoke out earlier this week for the first time since the divorce news broke, telling Extra that she's "doing okay."
"Whenever you're going through anything in life, when you step outside yourself and focus on others, that's always the best remedy for any situation that you'd rather not be dealing with," she said.