Prince Harry remembered the sadness he felt after losing his mother Princess Diana as he visited orphans in a poor area of Sao Paolo.
The royal admitted he felt "overwhelmed" during his trip to a social project run by the ACER charity in the suburb of Diadema, hearing the sad stories of the children left without parents – but said his own pain was "nothing" compared with their suffering.
Working with disadvantaged children, ACER is run by a Brit and aims to offer education, art programmes and cultural courses to those who are living in extreme poverty, as well as provide a library service.
Wearing a Brazilian football shirt, Harry took the time to play a game of football with the children there, but also listened to stories from the families who have been helped by the charity.
Speaking to journalists after the event, the Prince said: "I was completely overwhelmed and shocked. I've never blubbed in public as far as I can remember but I was pretty damn close. It was amazing to hear those stories."
Recalling his own childhood, he added: "There are two little girls - I'm quite emotional - just looking at them I wanted to talk about my own experiences. But there is no point because it is just so far removed.
"The bravery of them looking at me, smiling at me... I wanted to use my own experiences in a very small way to try to give them a bit of understanding about the fact that I see what you're going through. But you hear the stories and think that's nothing to what they have been through," he said.
Prince Harry plants trees in the Amazon rainforest
Earlier in the day the Prince worked up a sweat as he took a trip into the Amazon rainforest as part of his royal tour in Brazil.
The British royal visited Cota 200, a small village in the Brazilian Atlantic Rainforest which is in the middle of a conservation project.
The initiative, led by the Brazilian government, hopes to preserve the eco-system within the rainforest - which was also the subject of David Beckham's recent BBC documentary.
Harry appeared happy to get stuck in as he planted trees and met residents of the settlement who have lost valuable rainforest due to urban redevelopment.
Prince Harry tastes chef David Hertz's food during a demonstration
After the morning of hard work, Harry was rewarded with some authentic Brazilian food as he participated in a cooking demonstration with chef David Hertz.