The British family at the centre of a suspected poisoning tragedy complained of feeling woozy the morning before the two children died, it has been reported.
It was also reported that the 6-year-old boy, Robert, had collapsed at breakfast in the Corfu resort, but that the family's health later improved.
The British couple today emerged from comas thought to have been induced by poisoning, as authorities planned to carry out post mortems on the man's two children, found dead in the same hotel room.
Neil Shepherd, 38, and his partner Ruth-Emy Beatson, 28, from West Yorkshire, regained consciousness and were able to speak, although their lives were not yet out of danger, Greek state-run NET television reported.
Post mortems were being carried out today on Mr Shepherd's two children, who were found dead yesterday in a Corfu hotel bungalow alongside their comatose father and Ms Beatson. Authorities suspected the four had been poisoned.
Dr Stephanos Gasteratos, the Corfu hospital pathologist who suggested possible poisoning in the case, said full tests would be conducted at a university toxicology lab in Patras, on Greece's western mainland. Definitive results could take as long as 15 days.
Dr Gasteratos told NET television that "the first image by the toxicology tests shows that it is most likely a case of poisoning - not of food poisoning, but of a strong poison".
Mr Shepherd, Ms Beatson and the two children - Christianne, 7, and her brother, Robert, 6 - were found yesterday morning by a cleaner in their room at a luxury seaside resort in Gouvia, where they had arrived on Monday for a weeklong holiday.
Corfu police chief Anastasis Kakaroukas said there was no sign of forced entry to their room, struggle or other clues.
Hotel sources also ruled out food poisoning, saying that none of the hundreds of other guests had fallen ill. Mr Kakaroukas rejected speculation that airborne poisons, such as carbon monoxide gas, had been funnelled into their quarters via the hotel's air-vent system.
The children's mother, Sharon Wood, who lives in the same village as the couple - Horbury in West Yorkshire - was expected to arrive in Corfu tonight, while Ms Beatson's parents arrived earlier today.
The Louis Corcyra Beach hotel, about 5 miles north of Corfu town, remained open today but was scheduled to close for the winter on Tuesday, October 31.
Corfu, off mainland Greece's northwest coast, is one of the most popular Greek islands for vacationing Britons.
This is the third incident this year involving death or serious injury for a British tourist in Greece.