An offer to help a friend led to tragedy when a 16-year-old boy died and his mother was seriously injured in a road accident caused by the arctic conditions.
Gillian Gray, 46, from North Shields, Tyneside, agreed to make a 200-mile round trip to drive the friend's son to Leeds University.
She lost control of her Peugeot 307 on the A1(M) near Scotch Corner and hit the central reservation.
She and son Jake got out and were struck by a lorry travelling in the same direction which swerved to avoid their car.
Seven fire crews worked for more than three hours to free Jake from the wreckage but he was pronounced dead at the scene.
His mother was taken to Darlington Memorial Hospital, where she was said to be 'stable'.
Family members, including her 20-year-old son Daniel, were at her bedside yesterday.
Mrs Gray, of North Shields, North Tyneside, was separated from the children's father.
A friend of the family, who did not want to be named, said: 'I was absolutely devastated when I heard what had happened. I can't imagine what she's going through. She has another son, and they will both be beside themselves.
'From what I understand, she was actually doing a favour for a friend when the accident happened. Her friend had asked if she could take her son down to university in Leeds.
'She was just doing a friend a favour. They had the accident when they were coming back up to North Shields. The weather was atrocious. I'm still in shock.'
The incident happened one mile north of junction 56 on the northbound carriageway. Inspector Dave Sutcliffe, of North Yorkshire Police, said: 'An initial collision occurred between a Peugeot 307 and the central crash barrier which left the vehicle stationary. The occupants got out and were struck, in second road traffic collision, by a lorry going in the same direction.'
Jake, a keen dancer and musician, was a student at Newcastle College and dozens of shocked friends have posted tributes to him on the internet.
Traffic was at a standstill on the A1 in Newcastle on Tuesday as the deep freeze caused chaos on roads
Meanwhile, harsh weather conditions also claimed the life of Mary Priestland, a 90-year-old widow, who was found frozen to death after falling in her snow-covered garden in Barnsley, South Yorkshire.
Police believe Mrs Priestland lost her footing in the heavy snow and was unable to get back inside.
Neighbour Colin Stables, 71, said: 'It's very distressing for her family and it's obviously upset all the people who live in the old folks' bungalows around here. We try to look out for one another, especially when it's bad weather like this.
'Mrs Priestland was a smashing old lady and very independent. Her daughter wanted to take he to live with her in Bristol but she didn't want to leave her home and the village where she has lived all her life. Her husband had been a miner but died many years ago.'
Sledging was also the cause of two serious accidents. A 29-year-old man was in a 'critical condition' yesterday after sledging down a hillside on a mattress in the middle of the night and hitting a tree.
The man suffered serious head injuries in the accident at around 2.30am on Thursday and is currently in intensive care at the Royal Free Hospital in Hampstead, North London.
He had been sledging down the hill from the top of Alexandra Palace Park which is the highest point in North London.
While a man in his 20s was flown to hospital by air ambulance after being hit by a sledge in Broomhill Park, Strood, Kent. He was said to have suffered serious head injuries but they are not thought to be life threatening.
