Ben Affleck and Jennifer Garner were ''laughing'' and ''having fun'' during a day out together.

The estranged couple were spotted taking a stroll with their dog and three kids Violet, nine, Sera, six, and Sam, three, and looked happy together this week, despite rumours their split was caused by an affair Ben had with their kids' nanny, Christine Ouzounian.

A source revealed to PEOPLE magazine: ''They were laughing and talking to each other and looked like they were having fun.''

Their latest meet-up comes just days after the hunk - who was spotted with his family in Atlanta, where his former partner is filming new movie 'Miracles from Heaven' - celebrated his 43rd birthday with Jennifer, also 43, with their kids at Disney World in Orlando, Florida.

During the trip, the pair's relationship appeared strained, although a pal said they are trying to co-operate for the sake of their children, which is why he is continuing to wear his wedding ring.

The source said: [They] are both making the best of a hard situation.

''They did [the trip] together and the kids had a great time, which is what they both wanted.''

The pair announced their intention to divorce back in June following a decade of marriage.

In a statement issued by their publicists, they said: ''After much thought and careful consideration, we have made the difficult decision to divorce.

''We go forward with love and friendship for one another and a commitment to co-parenting our children whose privacy we ask to be respected during this difficult time.''