A DAUGHTER KNOWS WHO KILLED HER FATHER AND HIS FIANCÉE - CAN SHE PROVE IT?

AFTER FIVE YEARS ON THE STORY, "48 HOURS" IS THERE FOR THE ARREST AND TRIAL OF A WOMAN WHOSE CHILDREN TAKE THE STAND AGAINST THEIR OWN MOTHER

"MY DAD'S KILLER," SATURDAY, SEPT. 29

Hailey Sisco lived for a decade sure she knew who killed her father and his fiancée, but was unable to prove it. Police also felt they knew who killed Mike Sisco and Karen Harkness, though initially they didn't have enough evidence to make an arrest.

48 HOURS was on hand as police apprehended the suspect. It was another twist in a cold case the broadcast has been covering for five years - a story family members credit 48 HOURS with keeping in the spotlight. And, it is a case that tests a daughter's bond with her mother.

Mike Sisco and Karen Harkness were found dead July 7, 2002. The killer fired 11 bullets into the couple while they slept in Karen's Topeka, Kan., home. Their bullet-riddled bodies were found by Karen's father, who was visiting for a Sunday meal. He and his wife were there expecting Mike and Karen to tell them they were getting married.

"I felt it was overkill," Detective Richard Volle says on the season premiere of 48 HOURS. "It told me that there was some emotion involved in it�this was pure revenge."

48 HOURS Correspondent Richard Schlesinger reports, Dana Chandler, Mike's ex-wife, seemed like a perfect suspect. They'd gone through an ugly divorce and he ended up with custody of their two kids, Hailey and Dustin. Family members said Chandler had trouble coming to terms with the fact that Sisco had moved on in life without her.

"For 10 years, I've been thinking about justice, that she's gotten away with something that she did," Hailey tells 48 HOURS. Hailey adds, "She has a very complicated role in my life, because she is my mom, and she is my dad's killer."

"I know mom did it," Dustin says.

When 48 HOURS began following the story of the murders in 2008, it was a cold case. There was no physical evidence tying Chandler to the murders, no DNA and no witnesses.

With the case stagnant, the Sisco family began their own investigation. Hailey even recorded conversations with her mother hoping she'd slip up with key details. Hailey uncovered valuable information, but would it be enough to charge Chandler with murder? Schlesinger interviews Hailey and Dustin Sisco, Mike and Karen's families, Chandler's attorney, prosecutors and investigators about the case and the emotional trial.

Mike's sister, Cathy Boots, credits the prosecutors and Volle for not giving up. She also believes 48 HOURS played an important role. 48 HOURS was the first to publicly name Chandler as the primary suspect, and has been credited by the Sisco family for keeping attention on the case "I don't think anyone would have taken note and pushed it as far as it did without it being televised first," Boots says of 48 HOURS. "It was life saving for us."

48 HOURS: "My Dad's Killer" will be broadcast Sept. 29 (10:00 PM ET/PT) on the CBS Television Network. This broadcast is produced by Lourdes Aguiar and Sara Ely Hulse. Peter Schweitzer is the senior producer. Al Briganti is the executive editor. Susan Zirinsky is the senior executive producer.

"My Dad's Killer" marks the start of 48 HOURS' 25th full season. It's the third-longest running primetime series and has been the No. 1 non-sports program on Saturday nights for six consecutive seasons.

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