She said she never would have believed her project, during which she has travelled the country to interview more than 100 people, could have caused such a special meeting between long-lost brothers.
Joe took his wife, Rose, and their two youngest children down to see Ben - a World War II veteran - at his retirement home in Nelson.
"I walked towards him and we just embraced. It was just the most emotional moment I've ever had in my life.
"I'd never seen him cry, ever. He's the toughest guy I know. He did cry, and so did I.
"He's as bright as a button. He's exactly as he was when I saw him 35 years ago. He's still got his hair, he's still got his teeth, and he's still got his sense of humour.
"We spent a lot of time at the nursing home. We talked and talked and talked."
Ben and Joe's parents were from Ireland and the pair's oldest brother Arthur, as well as Ben, were born there before the family moved to Liverpool, England.
The young family then moved to Dunedin in 1922, and their third and fourth children Sally and Georgina were born, followed by their youngest, Joe.
The couple divorced when Ben was 17 by which time he had moved to Christchurch and he moved his four siblings up to be with him.
Arthur died in 2014, aged 99. Sally died around five years ago, and their sister Georgina lives in Wellington.
Ben later remarried, but his second wife has since died too.
Ben told of his abusive father - an alcoholic scarred by World War I - and loving mother.
"I have never known a peaceful time in my life. I've seen so much horror since I was a kid. There has never been anything else but that. It's very hard. You can't stand to the side of it. My mind goes into it, which stops me from sleeping. I don't sleep much."
He joked: "I couldn't believe my eyes when I saw my daughter with a man who turned out to be German.
"When I heard him speak and realised where he was from I wanted to kill him. I lunged at him and my daughter starting screaming not to hurt him. Over time I slowly accepted him.
"My thinking was wrong and I had to learn to understand him. We ended up becoming friends and he married my daughter. I even helped him on building sites."
Joe said his professional life covered everything under the sun - except, his wife said, cooking.
Joe said: "[Ben] believes he's going to go soon."
Through tears, Joe told him, "No you can't. You must hang on, because I'm coming back again, and I'll see you again, and this time I'll bring presents.
"It's the most incredible thing that's ever happened to me in my life. We now have the opportunity to be a part of each other's life again, which I didn't think would ever happen."
Ben told Hollis: "I seem to live forever. What the hell am I doing around here? I don't know why I am so lucky. I will have a long sleep pretty soon. It's about time."
Joe said he was sorry not to have taken a gift down for his elder brother.
