It's amazing how sometimes your brain will only register what it wants to see, and go on believing what it sees, even if it turns out to be completely wrong.
The house has two cars in the driveway. One an old classic, clearly cherished for many years, the owner one of the old breed of drivers, the tax disc a couple of years out of date now. The rust and dust are building up, but it still takes its pride of place out the front of the house. The other car is a shiny, new-looking car with a private number plate, the pride and joy of someone much younger who probably uses it daily and washes it once a week.
He's eighty-something years old, lovingly cared for by his granddaughter, at a guess in her twenties. She clearly adores him, and the love and admiration flows both ways. He's confused and in pain, having tripped and fallen down a couple of stairs. Whilst we assess his injuries, she's there, wiping his face, stroking his head, doing her best to comfort him. It looks as though he has fractured a hip, and the agony is made just that little bit more bearable by her presence, her reassurance, her love.
We're just the mechanism by which he'll get to the hospital, but she is clearly the power that will pull him through the experience. We give him some analgesia, scoop him up gently, and move him carefully to the ambulance.
She gathers some clothing together, finds his medication, checks the lights, the heating and the locks. Just before she's ready, I ask him a simple question.
"Is your granddaughter joining us in the ambulance, or is she going to drive up in her own car?"
As soon as the words leave my mouth, and I see the look on his face, the penny drops. The penny makes a loud, reverberating noise in my now empty head as I realise my error. Anyone can make that mistake, right?
I shouldn't have assumed. I don't any more.
I should have checked. I always do now.
I should have asked. I always will in future.
"That's not my granddaughter", he practically spits.
"That's my wife!"
There are those who learn from their own mistakes, and there are those who, without having to go through the pain of embarrassment, learn from mistakes made by others.
I hereby present you the opportunity to save yourself the blushes...