More than 10,000 people - many of them parents - have sought help for traumatised children after Christchurch's earthquakes.
Relationship Services Whaka-whanaungatanga (RSW) clinical leader Pablo Godoy said each child reacted differently to the quakes.
Reactions included bed-wetting, soiling themselves, tantrums, disruption to sleep and eating patterns, fearing places they had never been scared of before, returning to younger behaviour and nightmares.
"It's a really common reaction to stress," he said. "It doesn't mean your child is different and beyond the norm. The reason they're doing it is because they're normal.
"It's not the greatest way of looking at it but it's the reality of it. Children do act out, it's their way of saying something isn't right."