The mother of a teenage boy who was killed during a sleepover says she is grateful justice has been served for her son after nearly three decades.
Arthur Haines was sleeping in a house in Waterloo, in Sydney's inner south, with other children on April 9, 1998, when the house went up in flames.
The 13-year-old suffered severe burns when he became trapped on the top floor of the home and died in hospital 11 weeks later.
Police later determined the house fire was lit deliberately.
After more than 27 years, Gregory John Walker admitted unlawfully killing the schoolboy on Wednesday.
"I'm guilty, Your Honour," he told the NSW Supreme Court.
Arthur's mother Julie Szabo said it was the news she had been waiting decades to hear after the death of her cheerful "mummy's boy".
"All I ever