When your little girl wears this infant Supergirl costume , try not to confuse her for a bird or a plane as she zips around the house! This infant super hero costume is perfect because every little girl is a super girl! A fantastic baby Halloween costume idea, this Supergirl costume includes a removable cape and romper with under leg, snap closure. Infant size (1-2). This is an officially licensed Supergirl costume. TM & DC Comics. Availability: This infant Supergirl costume generally ships in 1 to 2 business days, but during the holiday season, please allow extra shipping time.