He felt privileged to be part of an organisation helping to build good young men, including 17-year-old Teraia Whatuira-Henderson, who gave a poignant speech about how much his buddy had helped him when his father committed suicide when he was 10.
Mr Apiata said: "There are a lot of us out there [without a father]. We all need a hand. Anything's possible in life, as you can see. Teraia standing up here, standing up straight, standing up tall with a strong foundation under his feet; speaking proudly, honestly to you all about his life."
Prime Minister John Key, whose father died when he was 6 years old, said he had always felt he had lived a rounded life. But he admitted there were things he had missed out on.
"I am the least practical New Zealander you will find. My wife always says: 'There are two sorts of people, honey. Doers and payers - and you are definitely a payer'."
The Big Buddy mentoring programme began in 1997, pairing big buddies with boys aged 7-14.
The foundation will help it become financially stable and match more boys with mentors.
Funding will go to areas that need it most, like South Auckland, Christchurch, Hamilton and the Bay of Plenty.
Foundation trustee and All Black legend Grant Fox said more than 580 boys had been matched with mentors since 2003 but 144 were still on the waiting list.