Personalized 4th Birthday Cute Penguin Toddler Long Sleeve T-Shirt. 4th Birthday Toddler Long Sleeve Tee - White has cute penguin in a party hat with the number 4 on its tummy for your child's fourth birthday celebration. 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.