"You don't talk to someone when they're trying to express something," she says. "You just listen carefully. Then they feel that they're being heard.
"Some people are really defensive. And that comes out as anger. The best thing is to listen until there's nothing left to say. Let them purge all those feelings, then come in with support."
But Mrs Christopher also makes sure she is well-prepared, particularly when telling parents that their child is a bully.
"That's quite a difficult thing to take on board," she says. "Some people are dismissive. They say, 'No, no, that's not my child.' That's when evidence is really important. You can say, 'Here are the facts.' And make sure all the answers are there, so you don't have to go away to find out."
With behaviour problems, she tries to avoid emotive language, terms such as "uncontrollable" or "tearaway". Her language is deliberately supportive - "I understand exactly how you feel."
And she purposely avoids placing blame on the family, even if problems are rooted there. "I don't judge what they're saying," says Mrs Christopher.
"We're here to deal with this together."
A meeting with a parent will always be followed up, either with a telephone call or a quiet chat in the playground. "Children are part of a family unit," she says. "What happens at home reflects what they're like at school. So we need to put in the support and listen to parents' anxieties.
"The child is our prime concern. But parents have to know we're here to support them too."