Sharon Wood and Neil Shepherd sat in anguish listening to testimonies at Wakefield Coronor’s Court that began on Monday to determine how her children died during a holiday on the island of Corfu almost a decade ago. Heating expert Thomas Magner, who was instructed to examine the scene by tour operator Thomas Cook, blamed “botched” pipe work for the carbon monoxide leak that caused the deaths of Bobby and Christi Shepherd, aged six and seven respectively.

The mother listened intently to details of the 2,000-pound holiday that her ex-husband had booked for her two children and his new partner. The family was put in a bungalow of the four-star resort where they were staying. On the third day of the trip in October 2006, both children felt unwell and dizzy. The children went to bed at 11.30 p.m. and spent a difficult night crying and whimpering before they died.

Three people have already been jailed for seven years over the deaths in 2010, but the inquest in Britain was only opened on April 27.

Three mistakes were identified that had led to the death of the children:

(a)    The boiler had been installed without a chimney to take out unwanted fumes;

(b)   A protection device to cut out the boiler if overheated had been disabled prior to the tragedy to avoid a worker having to come and relight the boiler when it was off;

(c)    A crude hole, made for air conditioning pipes, in the outhouse internal wall allowed fumes to pass into the bedrooms.

The children died of carbon monoxide poisoning. The inquest was told that there had been problems reported with the boiler five months earlier. The family were not supposed to be staying in the specific bungalow but were switched because the room they had been allocated was deemed unsuitable.

The children’s mother told the inquest that “this is not just a difference in legal standards abroad. This is gross negligence.”

“I think we have got to look a bit further up the chain of command of Thomas Cook,” she said. “We pay tour operators to protect our friends and family when they go abroad. Whereas, actually, they have done nothing more than you could do yourself.”

She told the court about how she was informed of the death of her two children while listening to the radio. She was officially told of her children’s death thirty minutes later by police who came knocking at her door. She was also told that her ex-husband and his partner were not expected to regain consciousness.

When she arrived in Greece, Wood was told that the next day was a bank holiday in Greece and was unable to see her deceased children for two days. Finally, On October 28, 2006, she saw the bodies of her children,  two days after their death.

The hearing is continuing.