Personalized 3rd Birthday Rainbow Number 3 Toddler Long Sleeve T-Shirt. 3rd Birthday Rainbow Toddler Long Sleeve Tee - Charcoal has cute number 3 with hearts and rainbow for a little girl. 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.