June 6, 2006 1:05 p.m. 6 pounds, 12 ounces St. Vincent’s Hospital Rosemary’s Baby, part deux? Stephanie Adler Yuan’s water broke two weeks before she was due, at the crack of dawn on a demonic date. Oh my God—we’re having a 6/6/6 baby! was her first thought. Luckily her firstborn, a petite, olive-complexioned girl with a full head of black hair, bore no Adrian Marcato–esque marks. “People just say she’s ‘ethnic’-looking,” said Mom, 31, a senior communication manager at Time Warner. Dad is her husband of three years, Brad Yuan, 37, a vice president at the advertising and marketing company G2 who’s already a pro at changing diapers and giving mini-manicures. Currently, little Ruby is glowing in the bassinet by her parents’ bed, but she’ll soon take over the second bedroom in the family’s Brooklyn Heights apartment. “She’s got the best room in the house,” Ms. Yuan said.