Valentino loyalist

Drew Barrymore is reportedly wearing Chanel to her upcoming wedding to Will Kopelman, but author Jill Kargman, who is Kopelman’s sister, will be clad in Valentino. Kargman wore a form-fitting black ensemble by the designer to her Joss & Mainsponsored book party for her new novel, “The Rock Star in Seat 3A,” and said she’ll wear another Valentino frock to the nuptials on June 2. Kargman celebrated her book with friends including Simon Doonan, Bettina Zilkha, Marisa Noel Brown, Aviva Drescher, Amy Fine Collins, Arie Kopelman, Dori Cooperman, Julie Macklowe, Liz Lange and Lizzie and Jonathan Tisc h at Lavo on Tuesday night.

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