Personalized Heart New Big Sister Newborn Layette. Future Big Sister Newborn Layette - White Announce that you are going to be a big sister with this blue heart design. 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