By Maggie Dolan BBC News

Kathy Pallant was taken ill with suspected gastroenteritis

A couple who previously stayed in the Corfu hotel room in which two children died from carbon monoxide poisoning also fell ill during their holiday.

Kathy Pallant and her husband Andrew stayed in bungalow 112 at the Corcyra Palace Hotel four days before siblings Christianne and Robert Shepherd died.

Christianne, seven, and Robert, six, were found dead on 26 October lying next to their father and his partner.

Mr and Mrs Pallant, from Bucks, were treated for suspected gastroenteritis.

'Lucky to be alive'

Carbon monoxide poisoning can be mistaken for gastroenteritis.

The hotel had said that no other guests fell ill.

My husband's a big man, and it took an awful lot of his strength for him to crawl round and get to the telephone for help Kathy Pallant

Mrs Pallant who lives near Leighton Buzzard told BBC News: "We feel very, very lucky to be alive. We feel dreadful about this family. It must not be hushed up.

"There must be other people who were taken ill. There were other people in there. We didn't see anything, but then did anyone see us being taken away by ambulance? I can't remember, I wasn't on this planet.

"My husband's a big man, and it took an awful lot of his strength for him to crawl round and get to the telephone for help."

Tour operator First Choice confirmed from the incident report logged by the on-site representative at the hotel that a Mr and Mrs Pallant were in the same room as Neil Shepherd, 38, his children Christianne and Robert and his partner Ruth Beatson, 27.

Mr Shepherd and Ms Beatson were found unconscious in the room. They are both in a serious condition but are recovering.

In a statement the operator said: "Mr and Mrs Pallant were staying in room 112 last week between 16 and 23 October.

"They were both taken ill with suspected gastroenteritis and were hospitalised. They were discharged the following day. They then travelled home on their original return flight."

Symptoms non-specific

The clinic in which the couple received treatment stated that the tests undertaken showed nothing untoward.

Toxicology expert Professor Alistair Hay said that the difficulty is that the symptoms associated with carbon monoxide poisoning are non-specific.

A spokesman for the hotel said no other guests had been taken ill

"You have headaches, you have aches and pains, you may feel very tired, and of course this could be attributed to a virus," he said.

The investigation into the children's deaths is centred around a gas boiler adjacent to the room and experts are now carrying out an examination on that, as well as air conditioning and water heater systems.

Scotland Yard detectives permanently stationed in Athens are working on the investigation alongside their Greek colleagues.

Greek police said they are planning to charge the owner of a hotel in Corfu, the maintenance manager and the air conditioning engineer with negligent manslaughter.

Hotel manager George Chrysikopoulos refused to comment on the cause of the children's deaths because of concerns over prejudicing the police investigation.

But in a statement, read in Greek and translated by an assistant, he said: "The hotel management are deeply saddened by this tragic loss of life and extend their most deepest condolences and sympathy to the family for their great loss at this time.