Personalized Shamrock Music Notes Toddler Long Sleeve T-Shirt. A shamrock comprised of green music notes is a fun design for family and friends during the March holiday of St. Patrick's Day and Celtic festivals. 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.