Personalized Sweetest Little Sister Toddler Long Sleeve T-Shirt. Who's the sweetest little sister? Cute Toddler Long Sleeve Tee - Black with adorable smiling cupcake with pink frosting and red cherry on top says SWEETEST LITTLE SISTER. 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.