Personalized Happy Pi Day Math Lover Party Newborn Layette. Pi Day math themed Newborn Layette - White has pi symbols in a pie. Fun gift for a geek, math teacher, college math major or any math lover. 100% combed ringspun cotton 5.8 ounce 1×1 baby rib sleeper. 3/8" flatlock binding at envelope neck and cuffs. Back sleeve flap to protect hands. Elastic opening at bottom. Infant: 0-3 Months