If You’re Happy and You Know It | 3D Animation English Nursery Rhymes Songs for Children by HD Nursery Rhymesbr br If You're Happy and You Know It - nursery rhymes from Dave and Ava! Clap your hands, stomp your feet and stay fit! br Dave and Ava is a series of 3D animated nursery rhymes especially for young children, ages 1-4. Each episode features a toddler boy and a toddler girl dressed as a puppy and a kitten, and their animal friends.