Born Free Mother's Day Carnival 2014 | Pictures

These Stars Know How to Have a Really Cool Mother's Day Party

Idina Menzel brought her son, Walker Diggs, onstage for a performance.

Claire Danes, Idina Menzel, Doutzen Kroes, and many more famous moms eschewed the traditional low-key Mother's Day brunch on Sunday to attend a kid-filled carnival in NYC for Born Free, an organization aimed at ending mother-to-child HIV transmission in Africa. Little ones and their moms were treated to performances by Ariana Grande and Idina Menzel, who brought her son, Walker Diggs, onstage with a large group of children to sing. Claire also took to the stage at one point, although it appeared that she and husband Hugh Dancy decided to leave their young son, Cyrus, at home.

The event was also chock full of fashion and sports stars, with fashion legends like Anna Wintour and Carolina Herrera rubbing elbows with New York Giants wide receiver Victor Cruz and the New York Knicks' Amar'e Stoudemire. Not every famous face celebrated Mother's Day with a fashion fete like this one — be sure to check out how celebrities honored their mamas (or were celebrated by their little ones) on Sunday!