LONDON • The house feels quiet and empty, pulsing with that deafening silence specific to death. We are a family in mourning. On a recent Friday, five of us got into the car and drove away in the sad knowledge that only four of us would be coming home.

We were taking a much-loved family member to "Switzerland", otherwise known as the vet (we hoped a little gallows humour might render the impending ordeal more bearable).

Sox, our cat, diagnosed with cancer four months previously, was now in pain - the time had come to do the "kind" thing.

Fourteen years ago, our son Oscar and I chose Sox for Francesca, our daughter. Oscar was 13 then and his sister was eight. Or rather, in the manner of these things, he had chosen us: We peeked into a basket of kittens and he pushed his little black and white face inquisitively into ours. "That's the one," we said together and brought him home to hide for Christmas.

As the years passed, Sox became firmly stitched into the tapestry of our home life, a constant presence whose personality enriched our family mythology.

It's hard to fully understand the connection between humans and their pets, but few would argue that cats and dogs are unusually perceptive. Sox could certainly sense when a trip to the vet was imminent. We had to make his cat basket appear by stealth and take care what we said in front of him.

At such times, he was referred to as "the gentleman" - as in, "What time is the gentleman's appointment?" "Do you know whether the gentleman is currently residing beneath the bed?" At other times, he was known as the Colonel, his whiskery demeanour somehow deserving of this respectful epithet.

There was a lot of playful nonsense associated with Sox, who was integral to the rituals of family life. My husband Simon, who hadn't wanted a cat because he didn't "trust" them, could be overheard talking to Sox when he thought they were alone.

Sox was a constant presence in my children's teenage years and beyond. Pets are always there, happy to see you and, unlike children, don't slam doors and roll their eyes when you speak. Sox's passing marks the end of an era.

Earlier this year, with some prescience, Oscar, now 27, said: "I don't know what I'll do when Sox dies - I won't be able to bear it."

I'd been wondering what a cat's life span was and, during the nightly ritual of reading in bed while stroking him, I found a lump on his rib. Exploratory surgery soon sealed Sox's fate - it was cancer.

Simon couldn't bring himself to enter the vet's practice. Oscar, Francesca and I kissed Sox and thanked him, having elected to leave the room for the fatal injection and dying of the light. The young vet looked like she was about to cry herself - even if it's your job, it can't be the easiest way to start the day.

Grief is grief, however you cut it. It's still the same familiar ache that swells from gullet to gut and fills the chest. The euthanasia permission form I signed showed that Sox was 14 years and 16 days old - this precise knowledge bore testimony to the continuity and simplicity of his life - one home, one owner, one vet. Later, we stroked his still warm fur and whispered our goodbyes.

But no one could have prepared us for the grief - a grief I feel almost foolish to speak of, but am encouraged to, on discovering how universally it is felt.

Grief is grief, however you cut it and comparing readings for pet grief as opposed to human grief on the griefometer serves little purpose. It's still the same familiar ache that only that old cliche time can heal.

I remember visiting the Peggy Guggenheim museum in Venice some years ago. The house has a small cemetery where she buried her beloved cats and dogs with a small monument dedicated to them. I remember finding it a little ridiculous - all that trouble for some dead animals.

Now I understand. It's a big thing to lose a family pet. There are books about pet bereavement, pet loss support groups, therapists offering counselling, delineated phases in the pet grieving process...

Will we get another pet? We're not sure we're strong enough. And we have ashes to scatter and a commemorative plaque to plant in our own garden first.

THE GUARDIAN