Oscar-winning actress Rachel Weisz and her former husband, “Black Swan” director Darren Aronofsky, celebrated their son Henry‘s fifth birthday together at Serendipity 3 Tuesday night. The exes, who are bringing up their son in the city after their marriage of nine years ended last year, opted for healthy filet of sole and veggies. The friendly former couple were casual at the East 60th Street eatery with Weisz in a denim skirt and ponytail and Aronofsky in shorts and a T-shirt. Weisz returned to town after she was spotted in Paris last week with new love Daniel Craig.

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