Personalized Little Monkey 6th Birthday Youth Long Sleeve T-Shirt. THIS LITTLE MONKEY IS SIX 6th birthday Youth Long Sleeve T-Shirt - Royal Blue with a cute smiling monkey holding a banana is perfect for a jungle or safari themed birthday. youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)