Personalized KC Cavalier Spaniel Toddler Long Sleeve T-Shirt. Cavalier King Charles Spaniel dog breed art by Contemporary PUP Artist, KiniArt (aka Kim Niles). © KiniArt™ - All Rights Reserved. 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.