Lauren Bush and David Lauren celebrated their engagement in style at the Water Mill estate of Anne Hearst and Jay McInerney. FEED Projects founder Bush and Lauren, son of Ralph Lauren, were toasted by party guests — beautifully decked out according to the white dress code — including Ralph, Ricky, Dylan and Andrew Lauren, Stephanie Winston Wolkoff, Amanda Hearst, Lauren’s siblings Ashley and Pierce Bush, Nacho Figueras and Princess Yasmin Aga Khan. Lauren’s proud mom, Sharon Bush, wished the cou ple “many grandchildren.” The September wedding will be at the Lauren ranch in Telluride. The bride will take the name “Lauren Bush Lauren.”