Skye Rae, 25, said the community had rallied around Mrs Samuels and her children.
"Alaina [had] tears, just so many tears. The people and the love shown, it really kind of speaks for itself."
Miss Rae, who was a member of one of the many sports teams Mr Samuels had coached, said the family had been out on Friday night for Mrs Samuels' birthday dinner.
"Alaina said it was just such a good night. The family had gone out for dinner and then they gave the kids [Dominic and Rueben] to Rosalie."
Mr and Mrs Samuels were continuing the birthday celebration when things went drastically wrong.
Last night, it still wasn't clear what the confrontation that led to a 44-year-man from Botany Downs allegedly running over Mr Samuels, causing multiple and fatal injuries.
Detective Senior Sergeant Albie Alexander said that contrary to earlier media reports, the men did not know each other.
"We are reviewing CCTV footage. We are still working through a number of witnesses and inquiries, which will take us a number of days."
Mr Alexander said the man did not hand himself in - as had been reported earlier. He and the vehicle he was allegedly driving was found by police late on Saturday.
He was arrested on "pre-existing unrelated matters" and will face obtaining by deception charges in the Manukau District Court today. It was not clear what charges he might face in relation to Mr Samuels' death.
Michael Spiess, owner of the 123 Casino Karaoke Bar, said he reviewed CCTV footage from inside the bar from the night.
"There was no indication that something would happen until the guy got run over. There was no indication there was a problem or would be a problem.
"He came in with his family to have a good time ... It's just a tragedy, what happened."
Miss Rae said Mr Samuels - who was nicknamed "Nutta" or "Nutts" - was her touch rugby coach.
"He opened his home up and his family up to everyone who was in the team - turned the team into a family, really.
"We'd have barbecues every Saturday after training and we'd have the whole team together. He brought people together."
Mr Samuels also loved to watch his boys on the sports field, and coached teams at both Howick College and Maraetai Beach School, which they attended.
"His sons play rugby," Miss Rae said. "He'd never miss a game, no matter how far they'd have to travel or how far the games were. You could guarantee that he and Alaina would be there supporting."
Miss Rae had earlier written on Facebook that she was "feeling so sick and lost in a pool of emotions".
Rueben, Mr Samuels' intermediate-aged son, also posted on Facebook: "R.I.P dad, you're in a better place."
Last night, a heart-shaped balloon bearing the words, "Hugs and kisses", and bouquets of flowers with messages about Mr Samuels had been placed at the entrance to the Gooch Place car park where he died.
It is understood Mr Samuels' body was already with his family at home.
A death notice in today's Herald says Mr Samuels will be there until Wednesday, when a service will be held before he is taken to Parirau Marae at Matakohe in Northland.
His funeral will be held at the marae on Thursday.
