Mr Bailey, 31, and his sister, 29, died on May 28, 2004 in a Deception Bay home.
Police believe a person or group of people killed the pair before their bodies were doused with an accelerant and set on fire just before 2pm.
Three triple zero calls were made on that day.
It is believed the first call captured Mr Bailey screaming in the background while a second call, possibly made by Ms Bailey’s four-year-old daughter Violet, captured an argument between a group of people in the background.
A third call came from neighbours who saw the house alight.
Emergency services arrived to find the house in flames and Violet wandering around the backyard, unharmed.
It was the call Violet made that allowed police to use cutting-edge voice identification technology to begin identifying suspects.
“As you can imagine, forensic and scientific processes have certainly advanced in the time since the murders and we have applied these processes to evidence located at the scene,” Detective Inspector Damian Hansen said last year when police renewed their call for information.
“The new information relating to the weapons located at the scene in conjunction with these advances leaves us confident we can achieve a positive outcome in this investigation.”
On Saturday morning, a 34-year-old Kallangur woman was arrested and questioned by detectives.
Police hope she is the first of several arrests in relation to the grisly killings.
“A number of people came forward with information and that has helped us greatly in solving this,” Inspector Hansen said.
“There are a number of other persons of interest who police will be speaking to in the coming days.”
Ms Bailey’s daughter, now 16, and the pair’s family have been waiting for a result like this and Inspector Hansen said it was an emotional time for them.
“It’s a very emotional time, especially for Violet,” he said. “It has been a long time coming.”
In 2006, the Queensland Government offered a reward of $250,000 for information leading to the arrest of the killers, with indemnity from prosecution for any accomplice who was not involved in committing the crime.
Inspector Hansen said the reward and indemnity were still available and urged anyone with information to come forward.
The woman has been charged with two counts of murder, one count of arson and one count of possessing a dangerous drug. She will face Redcliffe Magistrates Court on Monday.