Personalized T-Rex 4th Birthday Toddler Long Sleeve T-Shirt. T-Rex 4th Birthday! A cute T-Rex dinosaur holds a bright red balloon to celebrate the four year olds fourth birthday! Adorable gift! 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.