Personalized Santa Hat Tuba Toddler Long Sleeve T-Shirt. A sousaphone wearing a Santa cap is a funny gift design for tuba musicians, music teachers and students in tuba choir, concert and marching bands at Christmas and the winter holidays. A classic for Fall, Winter and Spring, these long sleeve toddler t-shirts are sure to be a staple in your child's wardrobe. Whether layered or alone, this t-shirt is soft yet durable enough to stand up to your toddler's playtime demands.