My three children have been badgering me for a puppy for some time. Pretty much every kid in their classes have pet dogs, so why not them?
I mean, if there was any doubt about how special a puppy is to a child, you only have to look at this little girl's priceless reaction.
But my rationale for refusing is that we live in a flat that is too small for the five of us and a dog would just add to the claustrophobia.
What I fail to explain is that I just don't fancy endlessly walking the thing at first light day in, day out (for it would become my role as I'm at home all day), nor do I relish the thought of constantly vaccing dog hairs from down the side of the sofa cushions.
I also really REALLY don't have an ambition to walk behind Rover urging him to squat and tremble and push one out for me to pick up with a freezer bag-gloved hand.
But there is another, more poignant, reason, which I'll come to. I'm only too aware that I am being massively selfish – something I feel hugely guilty about.
For I grew up with a dog. My three brothers and I got Sam – a springer spaniel-German shepherd mutt who we named after my dad's granddad - when I was around five years old.
He was a few weeks old and, as is the case with puppies, it was love at first sight. He was instantly our best friend, each of us staking our claim to be Sam's 'master' – yet always failing, because he was very much an independent spirit.
This was illustrated almost weekly when we'd take him for long walks on the moors above the council estate where we grew up.
At the halfway point, he would invariably think, 'Sod this for a game of soldiers' and then turn around and head back home. Alone!
We boys would finish our walk to arrive back in our cul-de-sac to see Sam sitting on our garden wall, his paws crossed in front of him like a lion, almost laughing at us as we staggered past the finishing line.
Virtually every photograph I have of me and my brothers when we were growing up has Sam in the foreground, being patted, cuddled, tickled, or just hanging out. Part of the gang. The fifth brother.
And then when I was 16, Sam became sick. Or old. Whatever. It had the same effect on him. His back legs went. He became lethargic, listless. He winced a little when you stroked him. He became incontinent. It was heartbreaking.
My dad knew what to do, but we wouldn't let him. He knew that the kindest thing for our beloved Sam was to take him to the vet's and have him put down.
But his four sons threatened to take a lump hammer to him if he so much as went near a veterinary surgeon.
But our dad knew best. He loved Sam as much, if not more, than we did. He couldn't bear to see him in agony any more than we could bear the thought of him being taken from us.
And so, one day, without telling us, our dad took a day off work while we were at school, and he had Sam put to sleep. Later, he told us that he held him tight in his arms as the vet administered the lethal injection.
It was the second time I had ever seen him cry (the first was at his dad's funeral).
My number two brother was so inconsolable he left home to stay with a friend's family for two days. He vowed never to forgive my dad for 'what he did' to Sam (he did) and I vowed I'd never have a dog again because the pain of losing Boy's Best Friend was too unbearable to contemplate going through ever again.
Instead, I named my youngest son after Sam. Seriously: I tell people he's named after his great-great-grandfather, but the reality is, he's named after my boyhood pet dog.
And now that boy – and his older brother and sister – want a pet dog of their own.
But I won't let them have one. Partly for all those selfish reasons I listed above.
But also because I don't want them to experience that terrible event of losing something you really love. And, in truth, I don't want to get a puppy, become attached to it, make it my best friend, and then lose it.
Because that's what dogs do. Their bodies age at the rate of seven years to our one. Then they die between the ages of 10 and 15 years. They are heartbreaking bastards.
Am I wrong to feel like this? Should I facilitate for my children the relationship I had with Sam when I was a little boy? Should I stop worrying about the size of our living space and the mess and poo picking-up and give my children the chance to form one of the most special bonds they will ever experience in their entire lives?
For the nurturing force is strong within them – and here's the proof: the summer sunshine and showers have created an orgy of mini-beasts on our roof terrace. I have never seen so many spiders and snails.
But rather than regarding the SaS as pests, my kids treat them as pets, to the extent that they give them names.
There are snails called Steven, and Gerrard, and Cristiano, and Ronaldo, and Rodriguez and James (monikered by my youngest, World Cup-obsessed, son).
And there are spiders that seem to live forever on their webs with names like Dave and Ian and Ben and Pete.
My kids pluck lettuce leaves from my wife's paltry pots to feed to the snails.
They catch flies to flick onto the webs of the spiders (or 'spidies' as they're known) in case the spidies don't manage to snare their own.
It's cute and sweet and lovely and infinitely better than having kids who pull the legs off insects.
And they definitely make me wonder how amazing my children would be if they had a puppy.
But then this happened last Sunday morning.
My wife and I were lying in bed when the 10-year-old came into our room with his lip trembling.
"What's the matter, love?" my wife asked.
"It's Dave," said our son.
"What about Dave?"
"He's....d..d...dead."
"It's only a spider," I replied, forgetting to engage my brain before I opened my mouth.
"But he's Dave," my son snapped back, and then ran out of our room.
"You don't understand," my wife said to me.
And she was right, but I wanted to, so I tried to make it up to my very sensitive son and told him that Dave had had a good life and now his death could go on to help the other Daves and Ians of this world.
"Let's put him in the composting bag and his body will break down and things will grow from his body," I said, in a very compassionate voice.
I don't think I've ever seen my son look more horrified.
"Recycle? Dave? But he's DAVE!"
And once again, he left the room.
But this time he wasn't sulking. He'd already decided what he should do.
He went to the kitchen and pulled off a kitchen towel from a roll, then he made a little burial shroud for his pet spider and wrote on it: "R.I.P. Dave The Spider."
And then he took it onto the roof terrace and found an empty plant pot, and laid Dave to rest right there.
And it made me think: "Hmmm, perhaps these kids NEED a puppy after all."
But then I thought: "If they react like this to the death of a spider, how the hell would they be if their pet dog died, as it will?"
I just don't know what to do for the best. Can you help?
More on Parentdish: Why a family pet is good for your family's health (Keith!)