Personalized 3rd Birthday Kitten Blue Youth Long Sleeve T-Shirt. I'm three! A cute blue kitty cat has a birthday hat and a cupcake with a 3 shaped candle. Happy 3rd birthday to the three-year-old! youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)