Personalized Monster Truck 3rd Birthday Toddler Long Sleeve T-Shirt. I'm Three! A red monster truck drives over the words. Great third birthday gift for your 3 year old who loves trucks. 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.