Two families meet at the Baltimore airport while waiting for their baby girls to arrive from Korea. The Iranian-American Sami and Ziba Yazdan, with Ziba's elegant and reserved mother, Maryam, in tow, wait quietly while brash and all-American Bitsy and Brad Donaldson, plus extended family, are armed with camcorders and a fleet of balloons proclaiming "It's a girl!" After they decide together to throw an impromptu "arrival party," a tradition is born, and so begins a lifelong friendship between the two families.

As they raise their daughters, the Yazdan and Donaldson families grapple with questions of assimilation and identity. When Bitsy's recently widowed father sets his sights on Maryam, she must confront her own idea of what it means to be other, and of who she is and what she values.