Caught in the Act

Khloé & Kourtney Throw Themselves a Book Release Bash!

11/21/2011 at 05:55 AM EST

Kourtney and Khloé Kardashian hosted a Gilt City-sponsored bash at a private apartment in N.Y.C. in honor of their debut novel, Dollhouse. The sisters smiled and snapped pictures with fans, who enjoyed a Central Park view and macaroons from Vendôme, as well as cocktails. "They were smiling and laughing with everyone," an onlooker says of the two. – Jennifer Garcia and Jessica Wedemeyer

NEXT: Double Date? Ashlee & Vincent Party with Liam & Miley in L.A.