Personalized Big Sister Duck Toddler Long Sleeve T-Shirt. Big sister duck is protecting her little duckling sibling with an umbrella while they sit in a puddle. Cute gift for any big sis! 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.