Jamie Hay, from Danesholme, was hit by a blue Fiat Punto while walking home from a wedding reception on the A6003, between the Rockingham Road roundabout and Vian Way, at about 10.50pm on Saturday.
He was taken to Kettering General Hospital with serious head injuries but died on Tuesday morning.
Numerous bunches of flowers have been left at the roadside where he was struck.
His mum Pauline said: "As I put on the card, it was a thank you for letting me be his mother.
"Basically he was everything you could want. He wasn't the perfect child, he was more than that. You could have had 10 of him in the house and still not had any trouble.
"There were so many people at the hospital on Sunday morning. He had so many friends and you can ask anybody, there's not a bad word to say about him. He's going to be missed."
Jamie, a civil engineer with Corby company Laurence McHugh, lived in Nansen Road with Pauline and dad Darren, older brother Ryan, sister Gemma, 19, and brothers Paul, 15, and Danny, 11, and was a doting uncle to his two-year-old niece KT.
The former Kingswood School pupil was a Manchester United fan and his mum said she is moved that all his friends from The Talisman pub in the Danesholme Centre have decided to wear Manchester United football shirts to his funeral
She said: "They all agreed to go to his funeral in Manchester United kits, even the people who hate Man United are going to wear them.
"They have spent a fortune on getting Jamie 21 or Jambo printed on the back of the shirts."
A coach may be used to take people to Jamie's funeral, the date of which has yet to be decided, and anyone who would be interested in booking a seat can contact Jamie's friend Rob on 07966 763960.
Witnesses to the collision on Saturday are asked to contact police on 08453 700700.
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The full article contains 374 words and appears in Northants Evening Telegraph newspaper.