Personalized 3rd Birthday Rocks Princess 3 Year Old Toddler Long Sleeve T-Shirt. 3rd Birthday Princess Toddler Long Sleeve Tee - Black has polka dot number three with princess crown design and 3 rocks slogan. 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.