Personalized T-Rx Toddler Long Sleeve T-Shirt. A cute green T-Rex dinosaur wearing a lab coat and stethoscope handing out prescriptions. Otherwise known as a T-Rx. Adorable gift for any medical professional who loves dinosaurs. 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.