Animals can be related somehow to others being the same kind bit different in their origins, like a cat and a tiger. Despite they are not the same kind they can be friends and play together at least they were much different in their size, but when they are the same is only something cute to watch.
This tiger cub plays with a fully grown cat, and despite they are distant cousins they can have a lot of fun being equals in size. The cat knows that the tiger is a baby so he let him get on top and play but babies are babies and the tiger later has to eat his milk.
This kind of friendships are rare to find but when we do they are cute and amazing to watch and enjoy it with a smile on the face.