Good point Jon.
But Spirit hasn't been around for a couple of days.
And Murphy hasn't actually been face-to-face with him (he usually slinks away and spends the day in our sitting room, or in the conservatory)
He's lost weight lately and I suspect triaditis (he's Minty's brother)
We'll keep monitoring him.
SmokeyPokey seems to sense he's not feeling well and licks his head tenderly.