Personalized Musical Triangle Toddler Long Sleeve T-Shirt. The musical triangle disappear in it's complexity text with the image of a triangle is a humorous play on the Bermuda triangle and a funny gift design for percussionists, music teachers and students in orchestra and concert band. 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.