Less than two months after the birth of her second child, actress Jemima Kirke unveiled her slim post-baby body at the Girls season 2 premiere party in New York City Jan. 9.

Held at New York University's Skirball Center, the 27-year-old channeled Stevie Nicks in a floor-length black velvet dress with gold embroidery. Kirke -- mom to daughter Rafaella, 2, and son Memphis, 7 weeks, with husband Michael Mosberg -- said she's able to juggle her career with motherhood by taking things "day by day."

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"I don't have a way," Kirke told Us Weekly. "I don't have any words of wisdom."

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Kirke was joined on the red carpet by costars Lena Dunham (in a Valentino jumpsuit), Allison Williams (in an Altuzzura ensemble with Giuseppe Zanotti heels and Fred Leighton jewels) and Zosia Mamet (in Moschino).

Dunham -- who created the hit HBO series -- said her writing is "a mix" of real life experiences and imagined scenarios. "Of course, the awkward, amusing and painful things that happen to you on a daily basis can't help but make their way in," she told Us. "But at the same time, as a writer, you have to use your imagination at least 15 percent of the time."

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One thing is certain: Dunham will once again be taking her clothes off. "I'll be less naked, but more naked," she teased. "I'll leave it to you to figure out what that means."

The second season of Girls premieres Sunday, Jan. 13, at 9 p.m. EST on HBO.

This article originally appeared on Usmagazine.com: Jemima Kirke Unveils Post-Baby Body at Girls Season 2 Premiere Party