Personalized Stays At My Birthday Party Long Sleeve T-Shirt. Funny birthday Long Sleeve T-Shirt - White with Las Vegas parody, party hat and balloons, says WHAT HAPPENS AT MY BIRTHDAY PARTY STAYS AT MY BIRTHDAY PARTY! 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