Two holiday firm representatives have been cleared of manslaughter after a brother and sister died of carbon monoxide poisoning in Corfu.
Robert Shepherd, six, and Christianne, seven, of Horbury, West Yorkshire, died at their apartment in October 2006.
Thomas Cook workers Richard Carson, 28, and Nicola Gibson, 26, were found not guilty by a court in Corfu on Tuesday.
But the manager of the Louis Corcyra Beach Hotel in Gouvia and two other staff were convicted of manslaughter.
Hotel manager Georgios Chrysikopoulos, head of the hotel technical department Petros Stoyiannos and hotel electrician Christos Louvros, were each sentenced to seven years.
Civil engineer Dimitrios Xidias was given two years on probation for breaching building regulations.
Outside the court, Mr Shepherd said: "We stand here today three-and-a-half years on and our fight for justice has culminated in those responsible being brought to justice.
"All of them in one way or another contributed to the catalogue of errors that killed Christi and Bobby and almost killed us."
He and the children's mother, Sharon Wood, said they believed Thomas Cook should shoulder some of the blame.
"They are the biggest travel company in the world," said Mrs Wood.
They urged the hotel owners to carry out their promise of demolishing the bungalow and replacing it with a suitable memorial "to our beloved children".
The three judges sitting at Corfu Town courthouse heard that the children had been on holiday with their father and his partner.
They were told that carbon monoxide fumes leaked into the bungalow from a "decrepit" boiler in an outhouse next door.
During the trial, lawyers for the hotel staff, boiler maintenance engineers and builders blamed each other for the deaths.
However, the three judges sitting at Corfu Town courthouse were told by Mr Carson's defence lawyer that his client was a "diligent" and "honourable" young man who had carried out his duties.
Miss Gibson's lawyer also said it was "unfair" to target her as she was the "last link" in the chain of responsibility.
Couple in coma
Thomas Cook said in a statement: "What happened in Corfu was a tragedy and the thoughts and sympathy of everyone at Thomas Cook will always be with the family and friends of Christianne and Robert Shepherd.
"We have always maintained that this tragic accident was the result of a unique set of circumstances, none of which could be the responsibility of the company or Richard Carson and Nicola Gibson.
"We believe that they should never have formed part of this court case."
The children were on a half-term holiday with their father, Neil Shepherd, and his partner, Ruth Beatson, who were both left in a coma as a result of the accident but survived.
Mr Shepherd described how, when his daughter became sick, he went to fetch a carrier bag for her to vomit into.
But he collapsed and woke up in hospital days later to be told his children had died.
The two comatose adults and the bodies of the children had been discovered by a chambermaid.
The court heard expert opinion that there was a "catalogue of failings" in installation and maintenance of the gas boiler.
Retired mechanical engineer Harry Rodgers, who inspected the bungalow, said it was the worst installation he had seen in 50 years.