Personalized Cutest Little Sister Youth Long Sleeve T-Shirt. Youth Long Sleeve T-Shirt - White says CUTEST LITTLE SISTER in bright, bold colors. Little hearts above the "i" in the words LITTLE and SISTER. youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)