Following further inquiries, Mr Kennedy was arrested at a home in Doonside, in Sydney’s west, about 5pm on Monday.
He was taken to Blacktown police station where charges are expected to be laid, police said.
Ms Swales told Nine’s A Current Affair program on Monday she hoped to get some answers about “what actually happened”.
“I’m very grateful for all the work that’s been done … to get justice for my son,” she said.
“As a mother, you never want to lay a child to rest and … it’s been a long time, it’s been long overdue.”
Detective Inspector Paul Quigg described the investigation as “protracted and complex”, lasting 16½ years.
He said Mr Kennedy was expected to be charged with manslaughter.
“Jordan never had a life, he was only 21 months old at the time of his death, he didn’t experience a life, education, and the finer things in life as you get older,” Inspector Quigg told A Current Affair.
“My main focus, and the focus of the entire team, was to find some form of closure to the family.”
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