Prince Harry admitted he was "completing overwhelmed" at hearing stories of young Brazilian children who have lost a parent to drugs, violence or prison, as he recalled losing his own mother.
The prince shared his experience after he was told about two sisters who were being cared for by their grandmother after their father was jailed and their mother was murdered.
He said he was close to "blubbing" as he listened to the harrowing tales.
"I was completely overwhelmed and shocked," Harry told reporters.
"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."
"It seems ridiculous for me to say to these kids, how lucky and fortunate they are, considering their situation. Obviously they are far from that."
"One of these kids here was five days old when he was left on the street by his mother, because she was on crack."
Harry met the family yesterday during a visit to the Association for Support of Children at Risk project to help young people.
The prince will later tour the Cracolandia area, notorious for its drug problems, with the mayor of Sao Paolo and the chief inspector of the Metropolitan Police as his tour of Brazil comes to an end.