Uma Thurman welcomed a daughter with partner Arpad Busson on Sunday, her representative confirms to THR.
The baby, who has not yet been named, was born Sunday in New York City. It's the first child for Thurman and Busson, who have been dating on and off since 2007.
The 42-year-old Thurman, who most recently guest-starred as movie star Rebecca Duvall on the NBC Broadway dramedy Smash, has a 14-year-old daughter, Maya, and 10-year-old son, Levon, with ex-husband Ethan Hawke.
Busson, a French financier-philanthropist, has two sons (Flynn, 14, and Cy, 9) with model Elle MacPherson, with whom he was previously engaged. They split up in 2005.
Three years later, he became engaged to Thurman but the two broke it off the next year; the pair eventually reconnected and announced Thurman's pregnancy this past February.