• Whāngai: 'it's the way we strengthen our families'
Umaga's documentary Sharing The Love follows a couple who become pregnant for the fourth time unexpectedly. They choose to whāngai their child to the mum's brother and his wife who have been trying unsuccessfully for a baby for 13 years.
It all started when Umaga's husband, former All Black Tana Umaga, got a text from his nephew.
The message read "my wife and I are expecting again. But we will be adopting our baby to her oldest brother".
"When we got the text, I didn't know if it was because they couldn't keep the baby, we even thought we'd take baby," Umaga told the Herald.
"Then we found out the reason why they were doing it.
"Straight away, because of my own experience, I knew this would be a really neat documentary."
Unlike most whāngai situations, where it is similar to an open adoption, Umaga didn't find out until she was 12.
"I was on the driveway at my home and my brother and cousin were having an argument about who's sister I was.
"That's how I found out. She [my cousin] was my biological sister.
"When I found out everyone started called me a whāngai."
Umaga's birth mum had been a struggling solo parent when she became pregnant with her fourth child. So Umaga was given to her birth mum's uncle and his partner.
Growing up in Wainuiomata, three hours away from her birth mum in Whanganui meant they never fostered a close relationship, but Umaga said she is happy with how she was brought up.
"I don't think she could afford to keep me. For me, it is what it is. I didn't emotionally get affected at all. I just accepted the situation. But a lot of people don't accept it
"A lot of them feel hurt. They might have felt like they were not wanted. I never felt like that. I didn't feel not wanted."
Having five older siblings was one reason Umaga was happy to be whāngai, it would be different if she had been an only child and missed out on being part of a big family, she said.
After being a full time mum for 10 years Umaga went back to work in 2013 as all her children were at school. She started as an executive assistant at KiwiRail before leaving to pursue "something I love".
She wanted to get into film and telling stories so she started a media degree at Auckland University but quit after a semester when she learnt she wouldn't get to touch a camera until her final year.
South Seas Film & Television School was her answer. She graduated in 2016 and her Sharing the Love documentary was the first idea she pitched.
"This is my first job.
"The title - Sharing the Love - that's what I want the audience to take away. That's what it's all about. It's about sharing a baby.
"And hopefully people get a better understanding of whāngai, a cultural insight."
Umaga and her husband Tana have four children aged from 11 to 24. She said she'd never be able to give away one of her own but would gladly whāngai someone else's child.
"I just know I wouldn't be able to. The connection is so strong. I just couldn't give one of my babies away."