Actress and model Elizabeth Hurley said she will campaign to make streets safer after her nephew was stabbed in south-west London.
Miles Hurley, 21, lost four pints of blood when he and a friend were attacked on 8 March, Hurley said.
Police said the two victims were attacked by a group of men after a verbal dispute when they were in a minor car crash.
Hurley said her nephew was still in “great pain” from his “shocking” wound.
On Instagram this weekend, Hurley said: “Thank you to all who sent such kind messages following the news that my nephew @mileshurley1 was viciously stabbed last week.
“His wound is shocking, he remains in great pain and he can hardly move.”
Hurley said her sister was an “amazing mother” and was looking after Mr Hurley and his friend.
“We need to make our streets safer and I want to be part of the movement to achieve that. I hope you will join me,” she added.
Her nephew thanked his family and fans for their support on his own Instagram page, where he shared a photo of one of his wounds.
He said he was still struggling to walk but was “slowly recovering”.
The Met Police said Mr Hurley and his friend were driving in south-west London when they were involved in a minor collision with another car.
After a “verbal altercation”, the pair drove away and parked on Ascalon Street.
But the group of men in the other car – described as black hatchback – arrived at the scene and attacked them before driving off, police said.
Both Mr Hurley and another 21-year-old man have since been discharged from hospital.
In an Instagram post, Hurley said the deepest wound Mr Hurley suffered “just missed severing his spine”.
“By some miracle no vital organs were damaged. We are praying that these animals are caught before they maim, or even kill, someone else,” she added.
“These are sad days.”
No arrests have yet been made and police are appealing for witnesses.