My family’s experience is that Father Christmas is rebranding himself, as Ebenezer. He seems increasingly peevish and unmoved by large requests. These days, he appears to stick to an utilitarian checklist, including only a couple of little toys. Presumably, he’s had it with the throwaway society - and with treading on Lego, as he tiptoes across the children’s bedroom floors.

A tip I’d give any new mother, with hindsight, is: don’t buy toys. I did. Now, my children have had 70 birthdays and Christmases between them. The house is awash with kit they don’t use and don’t need. We could start a toy shop - if I could find the missing pieces.

My kids aren’t tidy or careful with their belongings: they own too much. As do all their friends, from those who live in palatial splendour to those who live in council houses. There’s huge generosity around, in an era of high disposable income. It feels better to buy for our darlings than for ourselves. So I didn’t flinch when one son asked for three new golf clubs this Christmas, although he’ll grow out of them. At least they don’t have tiny pieces.

But are kids getting the message that pleasure comes in giving, rather than receiving? Hmm. As ever in parenting, the unpalatable yet inescapable truth is that we have to lead by example. One friend recently took her children to help with a Christmas party on a cancer ward. Her children commented subsequently that one of the most important gifts, which can’t be bought, is health. They had noticed how important friends and family were to children who weren’t sure whether this was their last Christmas, and that they didn’t feel like making present lists.

While I didn’t want to spoil Christmas for my sons, frighten them, or expose them to potential trouble, I did badly want them to grasp the concept of counting their blessings. So, I decided to try taking them to a night shelter for the homeless in a local town. For health and safety reasons the boys were too young to volunteer to help there. However, they could help me transport donations in kind, and see for themselves how lucky they, and their friends, all are.

First, I printed off from the website the list of gifts which the shelter needed. It was six pages long - and, shamingly, we had all of it. Even our dog, I realised, has two bowls (because a godparent gave one child a “paint-your-own-dog-bowl” kit) and doesn’t use one of them. Next stop, the larder. Of each standard food item listed, we had two or three to spare in our cupboards, I noted with some discomfort.

“What else do we have too much of?” I asked the boys. “Clothes, books, games, crockery . . .” they began. “There’s an old TV in the spare room,” offered the little one. “I’ll have it in my room,” added the teenager, grinning. Nice try, son.

Some of our excess - two mops, surplus mugs, discarded curtains - I suppose I’ve been holding on to for the time when the children leave to set up their own homes. But the chances are, they won’t want it then.

So, we filled our car boot with boxes of clothes, food, toiletries, the unused TV: the overflow of a house stuffed to the gunwales with worldly goods.

“It’s like weighing scales,” said the youngest thoughtfully. “We’re up here and we’re trying to make the homeless people balance more evenly.” The shelter was founded in memory of a man who used to sleep rough, under the very bridge we turn under on our way to town. This thought struck home, as we “passed by on the other side” in our warm car. It provides overnight shelter, food and recreational facilities to 30 homeless people. Of these, about 90% apparently have mental health issues, including drugs and drink problems.

We were shown the five small bunk-bedded rooms, where six homeless people sleep at a time. One room is for women. These are mostly young: thrown out by their parents, abused, or products of children’s homes. There’s one strikingly beautiful young girl, with long blonde hair. She plays the recorder rather well, yet begs on the street by day.

My children said little, as they were shown from room to room, but their silence was expressive. Afterwards, they commented on the kindness of the woman who ran it, yet they noted that the premises were “shabby”, “cramped”, “dark” and “underground”.

The sparseness of the life experienced by the shelter’s users is obvious. Many of them stand on the doorstep, or in the surrounding streets, smoking roll-ups and drinking cans of Carlsberg, marking time while they wait to return. Some chatted to us.

“Why do you think those people are homeless?” I asked my eldest.

“Addiction . . . neglect,” he suggested, looking at me with possibly a shade more appreciation than usual.

Did the children see why I had taken them there? “To show how much we should value what we have,” said one. “And for those people - although they’re very poor, at least they’ll know there are still some people who care about them in the world. I’m glad none of them asked me what I wanted for Christmas,” he added. “I wouldn’t want to tell them, ‘three new golf clubs’.”

Did it make the boys feel better? “Yes, when you’ve given something to someone else and they’re really happy to get it, or you know they really need it,” they concurred. They began discussing a whip-round at school, for stationery and T-shirts at school for Kenyan girl orphans, who had written an effusive thank you letter.

And did they think we should do it again? “Definitely. We should do it every year,” said the eldest. “It clears out the house,” he added with a twinkle, returning from sober mood to his usual teasing self.

A parent’s instinct is naturally protective; so initially, I’d been uncertain about bringing my children into the company of addicts with mental problems. But, once I’d started, it didn’t seem nearly as difficult as I’d imagined. I could picture some of the shelter’s users potentially being aggressive, or acting strangely - but, for the most part, they seemed deeply grateful to be treated like human beings. And, somehow, children can approach anything straightforwardly.

Of course, it is an affecting experience to leave the middle-class bubble of health and wealth and see what life might be like. And, in my children’s case, to meet people who are truly grateful for presents of food, toiletries, or your secondhand bedding or coat.

It made me resolve to carry on pruning every spare item from our house and take it to people who really have nothing. Not to the grand lady in the charity shop; but directly to people who need help. Most of my clothes would look better on that beautiful young girl, despite the glazed look in her eyes.

I hope I won’t get too self-importantly “busy” to return to the shelter soon. Perhaps the children will be less surly now, when boringly reminded of their privilege. And perhaps they may be less inclined, this year, to comment on the paucity of the presents provided by the Grumpy Old Man formerly known as Father Christmas.

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