Eleven-month-old Teyah was born with biliary atresia, a rare disease of the liver and bile ducts which occurs in infants.
Then Pewhairangi received the best news a mother could hear - she could save her daughter's life by donating part of her liver.
She had been told live donors had to be older than 21 - but Health Minister David Cunliffe cleared the way for the young mother to be considered her daughter's donor.
"When I found out she needed the liver transplant ... I stopped drinking, just went on a major health kick to get my liver healthy.
"They said it was the healthiest liver they had ever seen when they took it out of me."
Teyah was deteriorating fast in Auckland's Starship Children's Health hospital and Pewhairangi was by her daughter's bedside when she got the call.
"Her bloods were all over the show, she was just getting pumped full of everything to try and slow it down to try and get her past 1 [years old] really," she said.
"It was exciting and scary. I was just excited to be able to do it."
The mother and daughter had the operation in late May 2008 and Teyah took to the new liver "really well".
"Her surgery was over 12 hours because her veins were so small," Pewhairangi said. "Her surgeon had to get my surgeon in to help him reattach my liver to her tiny organs."
Initially, the mother-daughter duo had monthly check-ups, which later dropped to every three months.
"Now it is pretty much when they text me for a catch-up. We don't do much any more."
Today, the bright-eyed 11-year-old chases after her three younger siblings at the family's Te Rereatukahia Marae in Katikati.
The Katikati Primary School pupil is the school's cultural ambassador, plays netball and ran a half marathon on Queen's Birthday Weekend.
Teyah likes to take selfies, shop, stay at her nanny's house and listen to American pop singer/songwriter Taylor Swift.
She met the pop star after making a wish through the Make-A-Wish Foundation, a non-profit organisation that arranges experiences for children with life-threatening medical conditions.
"She was very tall," Teyah said.
Apart from the scars to remind them of the life-changing surgery 10 years ago, the pair remember the courageous event with a "Liverversary".
Teyah, Pewhairangi and her mum Lisa Murray go out to dinner at their chosen restaurant every year. They plan to celebrate their 10th Liverversary this month.
Teyah's three younger siblings - Melah, 7, Lily, 5, and Clayton, 1 - have to stay home.
"It is a special dinner for just us three," Pewhairangi said.
It is a simple celebration of life considering that a decade ago, having dinner with her daughter at 11 did not look likely.
Pewhairangi said her wider family had a history of biliary atresia.
"We had two pass away from here with the same disease. One died a year before Teyah was born," she said.
"I didn't take any of that pressure on though, that was taken on by my mum and my nan. They felt it the most, I was just trying to get her [Teyah] better."
When Pewhairangi fell pregnant with Melah, the midwife referred the baby to the doctor to check for any symptoms, but she was given the all-clear.
"So I pretty much didn't worry about it after that," she said.
Pewhairangi was thankful to her family for helping her push through the emotions. "I've always got someone there who can help with most things in my life," she said.
Murray said her daughter was a good mum.
"She sacrifices a lot for her kids. I am very proud of her."
THE STORY SO FAR:
May 2007: Baby Teyah was born
June 2007: At 6 weeks, bile accumulates in her liver. At 9 weeks, she has an operation to connect her small intestine to her liver.
Feb 2008: Teyah is rushed to Tauranga Hospital after she starts bleeding internally.
March 2008: Teyah is placed on the liver transplant waiting list, but her 18-year-old mother is told she is too young to donate.
April 2008: Pewhairangi undergoes tests to determine whether she can become a donor and is told she can donate part of her liver.
May 2008: Teyah celebrated her first birthday.
Late May 2008: Teyah and Pewhairangi undergo the operation.
June 2018: Pewhairangi family has grown to four children Teyah, 11, Melah, 7, Lily, 5, and Clayton, 1. Both mum and daughter are happy and healthy.
