Personalized 2nd Birthday Boy Outfit Submarine Toddler Long Sleeve T-Shirt. Cute submarine with number 2 for a toddler boy celebrating his second birthday party. A classic for Fall, Winter and Spring, these long sleeve toddler t-shirts are sure to be a staple in your child's wardrobe. Whether layered or alone, this t-shirt is soft yet durable enough to stand up to your toddler's playtime demands.