'Really?' she asked. 'How can they tell?'
Her cruel little bon mot was closer to the truth than she realised; it can be damn hard to tell. If the head is half-hanging off, it's straightforward, but often life doesn't end at a clear, discrete moment.
Sometimes it fades, like a summer night falling, gradually, slowly, softly, easily. The body does not just suddenly shut down and stop - like a car being switched off, parts of it remain warm for a while, and some of the cogs and wheels may continue to turn. The muscles may give one last twitch, the bowels one last playful gurgle, the chest one last heave, the pelvis one last suggestive thrust.
So at what point exactly has death occurred and the spirit left the body? In hospital, there are plenty of electronic gizmos, objective ways of confirming death, as well as plenty of second opinions.
But out in the sticks, a doctor has to rely on the traditional signs to make a correct diagnosis - no heartbeat, fixed and dilated pupils, absence of breath sounds, shunting in the retinal blood vessels (Don't we all check for this? No, seriously.). Make the call, trust your judgment and ignore the funny noises coming from the death-bed.
I'm sure we have all been in that kitchen, dispensing tea and sympathy, while Granny refuses to go gently into the good night. A relative rushes in: 'Granny's still breathing,' is the accusing shout.
Now is the time to hold your nerve, look them steadily in the eyes, take another scone (freshly baked is traditional, some conventions simply must be observed) and give the old lady time and space to comply with your diagnosis; breathing space, so to speak (maybe sneak back in later with a pastry-fork, just to be sure).
Nonetheless, at my funeral, just before they bury me beneath the old sod alongside my fathers and forefathers, could somebody please scratch my eyeballs with a pastry-fork?
Dr Farrell is a GP from County Armagh. Follow him on Twitter @drlfarrell.