For them, the extra time was a bonus. They visited tourist attractions and theme parks, and swam at their hotel.
But for their parents back home the delay was agonising, even though the children were thousands of kilometres from the scene of the attacks.
Yesterday, the agony ended with tears of joy as Mrs Harris and her husband, Peter, welcomed Matthew home at Christchurch airport.
"Words can't express how I feel," she said. "I'm just so happy to have him home."
The crisis stranded the children and their 11 caregivers in the midst of a panic-stricken nation.
Trust chairman and trip organiser Chris George said he and the children, aged between 8 and 15, were at a hotel in Los Angeles when news of the attack came through.
"It was an absolute shock. At that stage the safety of the children was paramount."
He said most of the children were too young to understand what was happening, but did not seem to mind the extended stay.
"I think some of the older ones knew what was going on. They were a bit wary at the beginning."
Koru Care is a charitable trust dedicated to making dreams come true for disabled and terminally ill children.
Trust spokesman Gavin Laing said the extra days cost the trust up to $25,000 in accommodation bills.
Given Air New Zealand's financial position he was not expecting any help from the airline, and public donations to the trust would be appreciated.
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: 0168 1800 932 8555
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: 0168 1800 245 0999
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: 0800 872 111
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