A cat will slobber over it's front leg and then rub it all around it's head to clean the places where it's tongue cannot reach but more often than not will team up with a family member in a symbiotic relationship for mutual head grooming. Here we see Shiloh taking care of her brother's head with licks and love and then he did the same with her head. And then they fell asleep together clean as whistle.

Watching cats go through life is an amazing thing to see. Their attitude is that's OK for them to share their home and point in time with the humans that are present. When you call a cat to come over to you, it ponders the request. If it feels like coming over to see you it will. If it doesn't it will look at you like you're nuts and then go back to whatever it was doing.