Personalized 3rd Birthday 3 Year Old Cowgirl Toddler Long Sleeve T-Shirt. Cute I'm 3 cowgirl themed birthday party Toddler Long Sleeve Tee - Pink with number 3 and cowboy hat. 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.