A third child has died after a fire swept through his home in Honiton in Devon on Friday.
The three year old boy had been taken to the specialist burns unit at Frenchay Hospital near Bristol but doctors were unable to save him.
A 17 year old girl and her 18 year old brother also died yesterday (Saturday) at the Royal Devon and Exeter Hospital.
A six year old boy and a 36 year old man were treated for the effects of breathing in smoke, but later discharged.
Police say the fire is not being treated as suspicious.
"It is with great sadness that police can now report that the 3 year old boy, who was taken to the specialist burns unit at Frenchay hospital, has today been pronounced deceased. Our thoughts are with the family at this time and the investigation to establish the cause of the fire is ongoing."
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