Scots College student Nathan Chaina fell into a flooded river at Kangaroo Valley and drowned on October 23, 1999, when he was 15 years old.

He and his older brother, Mathew, who witnessed the tragic accident, were taking part in a hike as part of a school camp.

A subsequent coronial inquest found that the school was liable for the death because it failed to properly prepare the students for the difficult conditions they faced and ignored the weather forecast on the day.

In 2002, Nathan's parents claimed damages for nervous shock and for the effect of their son's death on their cleaning products business.

They claimed they were so devastated by the loss of their son that they were unable to launch a new range of cleaning products which they believed would have taken the country by storm and earned them tens of millions of dollars.

[Rita Chaina in 2001 with her older son Matthew, who saw his brother Nathan drown.]

Rita Chaina in 2001 with her older son Matthew, who saw his brother Nathan drown. Photo: Brendan Esposito

During the course of a long and protracted hearing that has run off and on for 12 years, multiple experts have been called to give their opinions on the veracity of the couple's cleaning product claims.

The Presbyterian Church, which runs Scots College, admitted liability for Nathan's death but challenged the basis for Mr and Mrs Chaina's claim.

On Friday, Justice David Davies awarded the Chainas a substantially smaller damages payout than the $100 million they had asked for, ordering the school to pay just $492,373.

The sum does not include interest, which is in dispute and will be the subject of another hearing later this year.

The family appeared dejected by his honour's decision.

They have reportedly spent millions of dollars in legal costs.

The issue of who would pay costs was reserved.

smh.com.au