Personalized Mouse Youth Long Sleeve T-Shirt. A great finder, a great helper, and a great friend. Mouse Youth Long Sleeve T-Shirt - Black from "Dog and Mouse" by Michelle Nelson-Schmidt wants to help, not because she has to, but because she wants to. youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)