My cat, Dave, is washing. As he does so, he seems to grumble to himself, like an old man in a supermarket. Another thing he does that amuses me, is 'Treading'. All cats seem to do this, but only with their forepaws. Dave does this, but one of his back legs goes as well, as if he is trying to kick-start a motorcycle. He gets quite angry if you try and stop this.