Elisabeth was exposed to the gas for less than three hours
A landlord has been fined £20,000 for negligence after a six-year-old girl died from carbon monoxide poisoning.
Hussein Jajbhay, 50, had failed to have the boiler serviced for two years before Elisabeth Giaque's death and had missed two annual inspections.
Jajbhay was also ordered to pay £35,000 in prosecution costs when he appeared at Blackfriars Crown Court on Friday.
Elisabeth died in 2005 after inhaling the gas in her sleep at the rented house in Wimbledon, south-west London.
In a statement after the hearing, her father Nicolas Giauque said: "Overnight, three years ago, we lost our wonderful daughter and our sons lost their big sister.
"In less than three hours of exposure Elisabeth died from carbon monoxide poisoning in her own bedroom, where she had slept apparently safely for over two years.
"All owners, landlords, tenants or occupiers should be aware of the risks of carbon monoxide poisoning and regularly monitor their installation."
He said he and his wife went out leaving their three children with a nanny.
When they returned they found Elisabeth in a comatose condition and took her to hospital where she was pronounced dead.