24 years after Tim's death, it is still unthinkable that he didn't come home that day. Photo / Getty
On the day my son Tim was fatally injured by an IRA bomb, he had gone into town with a couple of friends to buy a pair of Everton football shorts.
It was March 20, 1993, and Tim - 12 years old and football mad - had left our home in Warrington for a day of innocent fun with his friends, just as on Monday evening the girls and boys at the Manchester Arena were dropped off by their parents for an evening of singing and dancing, unaware that a couple of hours later they would be fighting for their lives in hospital.
Twenty-four years after Tim's death, it is still unthinkable that he didn't come home that day, reports the Telegraph.
To kill a child - let alone multiple children and adults - is, quite simply, the most barbaric and callous act imaginable. And the devastation, the subsequent ripple effect it creates in every family who suffers this terrible loss is monumental.
I can still easily relive every minute after we learned that Tim had been injured in the explosion.
We had waited for three hours at the hospital before a surgeon came in, still wearing his scrubs. He was carrying an envelope, and when he opened it, two items came out.
He said to me: "Do you recognise these?" One was a watch with a canvas strap, the other a St Christopher chain."Yes," I said, "they belong to our son".
He said: "Well I'm terribly sorry, but I have to tell you I've been operating on your son for the last three hours; he suffered horrifying injuries and I don't think he'll live through the night, but if you will excuse me, I must go and see to him." And he turned and went.
Utter silence followed. I couldn't absorb what I'd heard. How could Tim possibly be about to die when he'd just gone out to buy a pair of shorts?
In those first two days, as my wife Wendy and I and our two other children, Dominic and Abi, sat together, at home and at the hospital, we were told there was a small chance Tim might survive.
But neurological tests would soon confirm our worst fears. We were told to prepare ourselves to turn off Tim's life support machine.
The injuries Tim sustained were too severe, and five days after the blast that had killed three-year-old Jonathan Ball instantly, our son died.
There may be many more fatalities this week. There are children in hospital now; some will be fighting for their lives. Their parents may well be sitting at their bedsides and no matter how bad the injuries are, they will be hoping and praying they will survive.
When your child is taken from you so suddenly and in such terrible circumstances, there is no rule book, no way of dealing with the tides of grief that threaten to engulf you.
As for coming to terms with it it, well, it is nigh on impossible to do so, ever. And certainly not in those early days, when you are so full of shock and bewilderment and disbelief that your child could possibly have ended up in this awful situation.
But speaking to other parents who have lost a child to an act of terror - as I did recently when I spoke to the parents of Lee Rigby - has helped me immeasurably over the years.
There is a terrible feeling of loneliness and isolation after an event like this, even when the deaths have been numerous. It can be especially helpful to meet other victims, when, as was the case with our son, there is no chance for justice.
The victims of Monday's terrible attack will never see the perpetrator put behind bars, but if my own experience is anything to go by, justice will be the last thing on the minds of those poor parents.
Wendy and I have never had justice for our son's death, nor have we ever craved it. For us, it was more important that his name was honoured by moving the peace process onwards.
Our son lives on through the charity we set up in his name. The Tim Parry and Jonathan Ball Foundation for Peace strives to help victims of terrorism, whatever age, whatever the circumstances of their loss, and it has been our saviour.
There is a terrible danger that parents sanctify their children and make them sound like little angels. And of course most kids have a side that you'd rather not broadcast. But Tim was the social fulcrum round which Dom and Abi congregated. He was a star, and when he went, he left a massive hole.
We talk about him constantly, and miss him terribly. Occasionally, we'll stick a home video on - I love to see him on film and remember him as he was.
Tim's name lives on through the foundation. I hope if he could see the good it has done, he would say: "good on you Dad, good on you Mum".