Kim Stoker, 42, had driven to Crowne Plaza Hunter Valley on Saturday night to pick up her cousin's two daughters, aged nine and seven, for a sleepover. Her 13-year-old daughter was with her.
"She said she missed the girls and asked could she come and get them for a visit," Heidi Stoker said.
The group was driving back to Ms Stoker's home near Maitland in a hatchback when the car collided with a sedan on a straight stretch of road near Tatler Wines at about 7.15pm.
The other car was driven by a 25-year-old Raymond Terrace woman, who had her five-year-old daughter and three-year-old son in the back seat.
Ms Stoker's younger sister, Heidi, said her family were astonished at the bravery of her 13-year-old niece, who pulled her two friends out of the car and used her mother's phone to call her father and the police.
The mother of four died from her injuries in the ambulance on the way to John Hunter Hospital.
A team from Cessnock District Rescue Squad used hydraulic cutters and spreaders to cut the driver's side of the sedan away and remove the Raymond Terrace woman.
She was taken by ambulance to Cessnock Airport, where she was transferred by Hunter Westpac rescue helicopter to John Hunter Hospital with limb injuries along with possible head, internal and spinal injuries.
The five children were treated on the roadside before they were also taken to John Hunter Hospital. Their injuries were not considered life-threatening.
Ms Stoker's daughter was still in hospital on Sunday night.
Ms Stoker's family and friends remembered her as a generous woman who could never stay angry at anyone.
"She was also so outgoing, would speak her mind to no end, loud, and you could hear her coming from a mile away," Heidi Stoker said.
She said her sister had been the glue that held her family together through recent challenges.
Ms Stoker and her partner of 19 years, Mark O'Neil, had lost their fourth child, a son, as a baby about 10 years ago.
Their 13-year-old daughter had a severe spinal condition that required regular appointments with specialists.
Mr O'Neil had become legally blind and stayed some of the week with his carer and Ms Stoker's widowed mother Debbie, in Cessnock.
Ms Stoker visited every day.
"She'd spend her last five dollars putting petrol in the car to come in and check on mum," Heidi Stoker said.
Mandy Perkins lived next door to the couple and their children for about 12 years and spoke fondly of the couple, saying they were due to marry in September.
Police attached to the Newcastle Crash Investigation Unit examined the scene, which is less than seven kilometres from Ms Stoker's home.
Inquiries are continuing.