In between her early brekkie TV starts and a busy family life in Sydney, Nat, 55, travelled north several times to get to know Kathleen.
Few people knew about her secret assignment, but those who did all asked the same question – did she do it?
“It’s so interesting that people are still so undecided,” says Nat, who adds that as a journalist, it’s her job to remain impartial.
Chatting to us ahead of the interview’s airing, Nat recalls sitting down on a cosy lounge as Kathleen snacked on chocolate and Coca-Cola. Even with the homey setting, Nat admits she was out of her comfort zone.
“I jumped at the chance because I’ve always thought it was a fascinating story,” Nat says.
RELATED STORY || Previously convicted child killer Kathleen Folbigg: "I'm innocent and my life in prison was hell"
She adds that the months-long research and preparation was “quite a challenge."
“It’s a different kind of journalism compared to what we do on Sunrise – you think about the story night and day for quite a few weeks and months,” she reveals.
“I haven’t really done long-form interviews like this very much … but I loved it.”
The second question on everyone’s lips, naturally, is “What’s Kathleen like?”
Nat tells us, “I was surprised by how strong she was, her lack of bitterness … she loves to hang out on her couch with [snacks] and she’s trying to work out how to put phone numbers in a smartphone.”
While Nat won’t be drawn on whether she thinks Kathleen is guilty or not, she does point out possible holes in the prosecution’s case.
“Many experts believe that if you read [her] diaries in their entirety, they don’t convict her,” Nat says.
“She was convicted for smothering her children … there is absolutely no evidence at all that she smothered her babies.”
As part of the exclusive, Nat also sits down with Lindy Chamberlain-Creighton, who opens up about the common threads between Kathleen’s story and her own.
“Lindy’s another woman who was judged for showing, in the public’s eyes, not enough emotion when she was convicted of killing a child,” says Nat.
WATCH NOW: Kathleen Folbigg Inquiry Recommended Over Children's Deaths. Article continues after video.
For now, Nat invites all Aussies to tune in and decide for themselves.
“There are so many twists and turns in this case – for 20 years, everyone else has spoken for Kathleen Folbigg and now for the first time we’re going to hear from her in her own words,” she says.
“People have judged that woman, now she gets to say what happened in detail as she pieces this puzzle together.”
7NEWS Spotlight airs Sunday 7 pm on Channel 7 and 7plus.
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