Peter Fankhauser, chief executive of the travel firm, has admitted the company failed in its handling of the tragedy and pledged to help the children’s parents move on with their lives.
He issued a public apology to them as the company seeks to halt a mounting reputational crisis over the way it has treated the family since the incident.
He said: “I’m deeply sorry - as a father myself - about the tragic deaths of Bobby and Christi Shepherd in 2006 on a Thomas Cook holiday.
“It’s absolutely clear that there are things we as a company could have done better during the last nine years - in particular how we have conducted our relationship with the family.”
Speaking after the release of Thomas Cook’s half-year results, Mr Fankhauser also vowed to apologise directly to the family of Bobby and Christi, from Horbury, near Wakefield, who died at the Louis Corcyra Beach Hotel on the Greek holiday island in 2006 when they were overcome by fumes from a faulty boiler.
Some customers have threatened to boycott Thomas Cook after it emerged that the firm received £3 million compensation from the hotel chain responsible for the incident, and following criticisms from the family.
Thomas Cook said earlier this week that it would donate £1.5 million to the charity Unicef, while the remaining £1.5 million went to its insurers for underwriting legal fees.
But the children’s parents, Neil Shepherd and Sharon Wood, hit out at the firm, saying they had not been consulted by Thomas Cook about the donation to Unicef.
The family have a particular children’s charity they have been supporting and to which relatives and friends have been donating in Bobby and Christi’s memory.
Last week, a jury at the inquest gave a conclusion of unlawful killing and said Thomas Cook “breached their duty of care”.
Following the inquest, the family blasted the company for failing to apologise directly, saying it was “disgraceful” that an apparent letter of apology from Mr Fankhauser was only brought to their attention by journalists.
Bobby and Christi, aged six and seven, died when they were overcome by fumes from a faulty boiler as they stayed in a bungalow in the grounds of the hotel with their father and his partner, now wife, Ruth, in October 2006.
An inquest heard that the youngsters died due to flaws with a hot water boiler in an outbuilding next to the bungalow where they were staying.
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