Blue Hoppily Ever After Sack & Hat Set Magnetic Me-Parent favorite sleeper gown hat set is a wardrobe staple for newborns. Tiny magnets down the front, allows the baby to stay in the gown during the diaper change. Magnetic closures make dressing easy. Eco-friendly TENCEL™ modal is silky soft, breathable, and gentle on sensitive skin. This fabric's temperature-regulating properties will keep baby warm in winter, cool in summer, and oh-so comfortable year round.