Erica Lumière knew she’d be pushing it (no pun intended) by attending a centennial weekend gala at her alma mater, Kent, the Connecticut boarding school, three weeks before a scheduled C-section. Sure enough, her water broke at the start of a football game. After narrowly missing giving birth on the Henry Hudson Parkway, Ms. Lumière, a freelance writer and former editor at Marie Claire, was surgically delivered of this dark, Mediterranean, brown-eyed beauty, a striking contrast to her golden-haired older brother Oliver, 2. “He loves his baby sister,” said Ms. Lumière, married for six years to Michael Howard, an investment analyst at Sanford Bernstein (both are in their 30’s). “He’s always saying, ‘She’s so cute, she’s so cute!’” The smitten siblings share a room in the family’s Upper West Side two-bedroom and are looking very fashionable. “When I was on staff, I spent more on myself,” Ms. Lumière lamented. “Now, I’m in jeans mostly. They’re in the fancy clothes.”