The actor is keen to look after Ange, who is expecting twins in August.
It is thought he spent the afternoon on the beach with adopted kids Maddox, 6, Pax, 4, and Zahara, 3.
They were joined by singer Bono and actor Robert De Niro, 65.
'Bono and Robert De Niro are really good friends and they hang out in the south of France together every summer,' a source tells E! Online.
'The kids looked like they were having a great time and none of the locals bothered them or took any notice of them.
'It was a fun afternoon out for all of them.'
Brad, 44, and Ange, 33, are also parents to baby daughter Shiloh, 2.
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