Personalized Musician Mom Worlds Best Long Sleeve T-Shirt. My Mommy is the Worlds Best Musician Long Sleeve T-Shirt - White gift for children has colorful lettering and earth logo. Pre-shrunk 100% cotton 6.1 ounce long sleeve t-shirt. Double-needle stitched neckline and sleeves. Quarter turned. Shoulder-to-shoulder taping. Adult: S, M, L, XL, 2XL, 3XL