The alleged attack with scissors during a fight with the other boy was completely outside his usual demeanour, the source said.
"It's just not in his nature. He gets frightened and hates confrontation. He hates violence.
"He's such a great boy, I don't know what came over him. He's not dangerous, he's not what people think he is. He has a heart of gold."
He had been bullied at the Pacific Christian School in Mangere for "over a year now", and might have finally acted out.
At the police station on Tuesday afternoon, after the fight that morning, the boy was in tears, the source said.
"He said the [other] boy was mocking his mum and dad. I think ... he realised. I could see the remorse on his face. He was beside himself."
The boy, also 11, had been involved in other fights at school but always only "to protect himself", the source said.
The school had been made aware of the bullying by his family in the past couple of months.
"He's ... been bullied for over a year now and he's just snapped. It doesn't matter how old you are, a human being can only take so much," the source said.
The injured boy remained in a critical but stable condition at the Starship hospital last night. His family would not comment on the incident yesterday.
School principal Lisita Paongo also declined to comment, saying she wanted to focus on helping the pupils involved, as well as those who had witnessed the stabbing.
Detective Inspector Dave Lynch said witnesses still needed to be interviewed. No charges had yet been laid.
Katrina Casey, Ministry of Education head of sector enablement and support, said its traumatic incident team had been providing support, "and they will continue to provide support for as long as it is needed".'
MP's comment 'naive'
It was naive to suggest there wasn't a problem in an area where two school-related stabbings occurred yesterday, a child psychologist has said, after a comment from the electorate's MP that "boys will be boys".
Mangere MP Su'a William Sio downplayed any problem in the area when he appeared on TVNZ's Breakfast show yesterday morning.
"I think it frightens anybody when you hear of young children in a situation where allegedly there is a weapon being used, but that's symptomatic of a community that has a high proportion of young people in it.
"Whenever you've got young people, you're going to get this kind of situation from time to time, although most of us do not accept that the allegations of weapons would be part of a schoolboy fight.
"I would just say to those boys: 'Grow up,'" Mr Sio said.
However, child psychologist David Stebbing said it was probably naive to suggest there were not issues with young people's behaviour in the community.
"For millennia kids have had fights ... but stabbing people isn't normative. If you're looking at the meta level, then obviously you are talking about deprivation, family difficulties - all the things that you associate with poor outcomes for kids."
- Brendan Manning
