Personalized Dinosaur 3rd Birthday Adult Sweatshirt. Happy birthday! A cute dinosaur wearing a birthday hat peeks around a 3. Cute gift for the three year old's 3rd birthday! Stay warm and stylish with this classic adult sweatshirt, perfect for everyday comfort. Crafted from soft, durable fabric, it features a relaxed fit for added coziness. Whether you’re lounging at home, running errands, or enjoying outdoor activities, this versatile sweatshirt is a wardrobe essential for any season.