Personalized It's My Birthday Letters Toddler Long Sleeve T-Shirt. Toddler Long Sleeve Tee - White says IT'S MY BIRTHDAY in colorful letters with birthday candle and streamers. 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.