Personalized Dog and Mouse- Best Friends T-Shirt. Show off your bestie with Dog and Mouse- Best Friends T-Shirt - White, from the children's book "Dog and Mouse" by Michelle Nelson-Schmidt. Everyone loves our Custom T-Shirts! Wardrobe essential for looking good, 24/7. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar. Shoulder-to-shoulder taping. Double-needle stitched sleeves, bottom hem and front neck. Note: greys are a cotton/polyester blend.