This video is delightful!
It would appear that this mother cat is old friends with the dog, and just like us humans when something amazing happens in our lives we like to share it with our friends, old and new. So here is this lovely black mother cat bringing her kittens to meet an old and well thought of friend.
I love the bit at the end when the two of them begin play fighting just like the old days. These two obviously have a very special friendship that will last forever!