This story was originally broadcast on April 23, 2011. It was updated on March 17, 2012.
Produced by Lourdes Aguiar, Jenna Jackson and Jennifer Simpson Ashmawy
SOMERVILLE, Texas - Before the early morning hours of Aug. 18, 1992, the police in Somerville, Texas found six bodies in the burned rubble of what used to be the Davis home.
"This was such a horrific event in that town and continues to be an event that really haunts the people of Somerville..." Texas Monthly reporter Pam Colloff told "48 Hours". "This was a family that almost everyone in town knew, liked, respected."
The victims: A grandmother, her daughter, and four grandchildren who were staying with them.
Colloff is still moved by the fact that the family never had a chance.
"There was Bobbie Davis, the grandmother to the four children who was bludgeoned and then stabbed to death," Colloff explained. "There was 16-year-old Nicole, her daughter, who was a high school student and athlete, who was bludgeoned and shot. And then there were the four grandchildren. They were 9-year-old Denitra, 6-year-old Brittany, 5-year-old Lea'Erin and 4-year-old Jason."
Glenda Rutledge is Lea'Erin and Brittany's mother.
"And my daughters, "Rutledge sighed, "were exotically beautiful. Beautiful...They were my legacy..." she continued in tears. "I was so looking forward to the chance to get it right... You know, to raise strong, sure, confident, successful women. You know, I wanted to do that so bad."
Rutledge's ex-husband, Keith Davis, lost almost his entire family that night.
"I mean these were little babies, and - and my mother, who... you know, who we adored, who was the center of our life," he said.
He was convinced it was a random crime.
"I just couldn't imagine someone from that area harming anyone in my family, 'cause we had never...we didn't have any enemies, we hadn't been in any trouble," said Davis.
Roy Rueter lived and worked not from the murders. Five days after the crimes, he remembers hearing there was a break in the case.
"I could hear the radio and the news would always come up..." he recalled. "And - it was early in the morning and they came up and they said, you know, arrest had been made...and they said uh - Anthony Charles Graves, age 27."
Anthony Graves was one of Rueter's best friends. Graves had worked for him for a while at his machine shop and the two became so close that Graves had even been in Rueter's wedding party.
"And it just it just freaked me out," he told "48 Hours Mystery" correspondent Richard Schlesinger. "But my immediate thing was, yeah, right. No way. And what - you know, what - what could possibly be going on here, you know?"
"You didn't believe it?" Schlesinger asked Rueter.
"Well of course not. Absolutely not."
Rueter knew Anthony Graves as a gentle man, a father of three. He was now hearing his friend was a murderer - of women and children.
"In my heart, my convictions were that's impossible," he said. "Anthony would never do that. Anthony would never - hurt or raise a hand to a woman. And especially not a child, especially the way he loved his children."
And when Graves was arrested, he seemed equally stunned.
Justice of Peace: You are charged with the offense of capital murder...
Anthony Graves: Who? (raising his hands to say stop) Capital murder? Me?
Rueter was so sure of his best friend's innocence that he put up $10,000 of his own money to hire a top lawyer for his upcoming hearing, convinced it would all soon be over.
"There's no way they have anything," Rueter insisted. "They don't have anything."
Police did have the words of Robert Carter, the father of the youngest victim: 4-year-old Jason. Investigators had grown suspicious when they noticed Carter had injuries that were hard to explain.
"At the funeral for the victims, Robert Carter showed up heavily bandaged on the left side of his face and his left hand...and the bandages were covering up severe burns," said Colloff.
Carter claimed he burned himself after his lawn mower blew up.
"The Texas Rangers obviously noticed Mr. Carter at the funeral," Colloff explained. "It was difficult to not notice. And they visited him at his house after the funeral and took him in for questioning."
Carter insisted he had nothing to do with the murders, but the Rangers had learned that he had a motive. Carter was married, but he had recently been served with a demand for child support from another woman, the mother of his son, Jason. Investigators believe Carter went there to kill Jason..
"He very clearly wanted his 4-year-old son dead," said Colloff.
After the murders, investigators believe Carter set the fire to cover his tracks, but from the beginning, they believed he must have had help. There were so many victims and so many weapons.
"There was a gun, there was a knife and there was a hammer," Colloff said. "And, investigators found it difficult to believe that one person could have wielded three different objects in killing six different people."
The Rangers interrogated Carter for hours and he finally gave them a name.
"During his interrogation, Robert Carter placed himself at the crime scene, but he said that he had not taken part in the murders himself. That the person who had committed the murders was a man named Anthony Graves, who was his wife's first cousin," said Colloff.
Within hours, Anthony Graves had been arrested and taken to the police station. He took a lie detector test and failed.
At first, there was little more than Carter's word that tied Graves to the case. But investigators would soon get help from the last place anyone would expect: Anthony Graves' best friend.