We hated Christmas. This was the official family line when I was young. The family was Mum and me; my stepfather was an unspoken-about appendage. The three of us co-existed in a tiny house in Bath to which no one ever came except a fat man from the Labour party who renewed memberships once a year.

Mum had a postcard on a noticeboard with a cartoon of a woman addressing a group of bemused guests: "No food: couldn't be bothered." She was as loving a mother as has ever lived. But she thought her love for me would be enough – and the food was not good. Every year the three of us ate Christmas lunch in silence: a frozen turkey, packet stuffing, roast potatoes and sprouts. There was cake in the afternoon and we watched Morecambe and Wise in black and white.

In later life I'd volunteer to work at Christmas, eventually rising to be Boxing Day news presenter on BBC1. This could not have happened without those years of packet stuffing.

Then I met Sarah. My wife is ebullient and fun and wishes every day was Christmas. She was born to cook Christmas food. When we moved to America eight years ago the tradition continued and the food took on the rich accents of the November Thanksgiving dinner. It still revolves around the turkey but focuses on autumn vegetables – pumpkins, sweet potatoes and squashes.

Then, last year, on a perfect winter Washington day, hours before our Christmas routine began, we took our eight-year-old son, Sam, to the doctor. By nightfall he was in hospital with Type 1 diabetes. He could only eat with injections of insulin to deal with the food. He came home with a blood test kit and a packet of syringes. Eating could never again be a source of casual enjoyment. Sarah went ahead and cooked, and two sets of friends came round. The house smelled of food. Plates heaved. For Sam there were frantic efforts – which I don't think he saw – to distract him from dishes that would see him back in hospital. Late in the evening he said he was still hungry so I carved him some turkey and thought I would take a photo. Sam smiled and gave me a thumbs-up.

"I'll be OK," he seemed to be saying. We had managed to feed our son on Christmas Day, and he – with the staggering resilience of the young and brave – had eaten his meal and pronounced it good.

• Justin Webb presents the Today programme on Radio 4. His book, Have A Nice Day, is published by Short Books