Shop for the very best in Seattle Mariners kids gear and apparel on MLB Shop. We have Seattle Mariners jerseys, shirts, baby creepers, toys, collectibles, and more for your child. Browse items perfect for newborn gifts all the way to older youth jerseys and apparel. Welcome your kids into the Seattle Mariners fan club with their very own gear and begin a fun tradition that can last a lifetime. Whether you're shopping for your kids or looking for an awesome gift, MLB Shop is your source for Seattle Mariners kids gear.