Personalized Shamrock Irish Flag Youth Long Sleeve T-Shirt. This colorful Irish flag logo with green shamrock clover is a lovely gift for any Irish friend for St. Patrick's Day. It comes on a holiday Youth Long Sleeve T-Shirt - White. youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)