Personalized Future Trombone Player Music Toddler Long Sleeve T-Shirt. Trombone Toddler Long Sleeve Tee - Kelly Green musical quote gift says when I grow up I wanna be a trombone player. 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.