Personalized 3rd Birthday Mermaid Party Newborn Layette. 3rd birthday party Newborn Layette - White with blue mermaid tail for a little girl turning 3 years old. 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