A five-year-old boy has become the latest victim of a house fire which had already claimed the lives of his eight-year-old sister and a 33-year-old mother.
Justine Collison has been named by police as the mother, with her two children being named as Isabella, who died in the blaze and Harvey, who died in hospital.
It is understood the 34-year-old man who remains in a serious condition in hospital is Mrs Collison's husband Gavin.
Her mother Diane Fletcher, 53, was led to safety from the property in Woodhill Road, Collingham, near Newark.
Emergency services were called at around 7am on Saturday to reports of a blaze at the home, which is to the north of Newark in Nottinghamshire.
"Tragically a boy, five, who was rescued from the house and taken to hospital has died," Nottinghamshire Police's Area Chief Constable Rich Stapleford said.
A 34-year-old man remains in hospital in a serious condition. All the casualties were members of the same family.
A joint fire and police investigation is taking place to determine what caused the fire.
Constable Stapleford said the blaze was particularly close to home for the firefighters at the scene.
"Collingham is a very close knit community and this includes some of the fire crews who responded. I know this news will hit the village very hard indeed," he said.
"I speak on behalf of all the emergency services who were in attendance when I say our thoughts are with the victims, their families, friends and the community of Collingham at this difficult time."