Personalized Behind Muggles & Mom T-Shirt. Muggles and Mom westie terriers - A behind the scenes look from the making of children's book, "MUGGLES' NEW HOME" by Author & Illustrator, Kim Niles 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.