On a quiet night in 1991, Detroit police answered an unnerving call.
A man told them he had just repeatedly stabbed his wife.
She had been six-months pregnant.
Now, she was dead.
When the officers arrived at the house, Gregory Green was calmly waiting. He didn't place the call to get involved in a fiery shoot-out. It was not a trap. He placed it for one simple, chilling reason: he had just murdered his pregnant wife, and he was ready to be arrested and pay for his crimes.
After Green pleaded no contest to second-degree murder, he spent 16 generally uneventful years in prison - only once, in 2002, did he present any disciplinary issues when he fought another inmate.
"He was denied parole four times for various reasons, but they all centered around the main idea that he had not shown remorse for his crime, had not gained adequate insight, and had a lack of empathy," Chris Gautz, spokesman for the Michigan Department of Corrections, told the Detroit Free Press.
Finally in 2008, after completing cognitive-based rehabilitation programmes, he was deemed ready to re-enter society and released into the world.
Once free, he began a new life.
In 2010, he married a woman named Faith, who had two children. With her, he quickly fathered two of his own - one was five years old, and the other turned four just two weeks ago. Green and his wife held a birthday party for her at their house on Hipp Street in the Dearborn Heights suburb of Detroit.
"All the relatives were here," their neighbour Ronnie Jones, who witnessed the party, told WWJ. "They've had two or three parties this summer where they had get-togethers. I just figured they were a regular family."
On September 1, he was issued a learner's permit in preparation for a commercial driver's license.
But not all was well.
His history seemed doomed to repeat itself.
Faith had filed for divorce in August, according to the Associated Press. And on Wednesday, WDIV reported, she served him with divorce papers.
On Wednesday night, police received another unnerving call.
Green told them he had killed his entire family.
When the officers arrived at the house, Gregory Green was sitting on the front porch, calmly waiting. He didn't place the call to get involved in a fiery shoot-out. He was ready once again to be arrested and pay for his crimes.
The horrible scenes were almost identical, but Wednesday's body count was quadruple that of 1991. All four children were dead, and his wife was suffering from gunshot wounds. Slash marks covered her face and throat.
The two young girls - 5-year-old Koi and 4-year-old Kaleigh - he had allegedly placed in a car. A hose Green snaked through the window attached to the tailpipe of his car, carrying carbon monoxide into the vehicle.
He waited for them to die - the colorless, odourless gas causes flu-like symptoms such as headache, confusion and dizziness, before those afflicted drift off into unconsciousness and eventually death, according to the Centres of Disease Control and Prevention.
Then, police say, he carried their small corpses upstairs to the bedroom and placed them in their beds, as if they were simply sleeping. When police found them, according to the Detroit Free Press, they had no visible wounds.
They were just still.
His wife he allegedly tied up in the basement before cutting her face and throat. Then, he shot her in the foot, and left her there to bleed out.
First, though, police say he made her watch as he took his two stepchildren - 17-year-old Kara, who WDIV reported was a cheerleader and a National Honour Society member, and Kara's 19-year-old brother Chadney - and shot them both execution-style.
Police took Green into custody without incident. Faith was rushed to the hospital and is in fair condition.
On Thursday, Green was charged with four counts of first-degree murder in their deaths, a count of torture and one count of unlawful imprisonment for tying his wife up in the basement. He is also charged with three other felonies, including assault and being a felon in possession of a firearm.
He has not entered a plea, and he is being held without bond. It is unclear if he has an attorney, but the Associated Press reported he didn't have one with him in court on Thursday.
There aren't many details as to Green's potential motive.
"The call was made by the suspect himself," Capt. Michael Petri told reporters in a press conference, according to People. "All of this seemed to have stemmed from a domestic violence-related incident."
Domestic violence was allegedly an issue in the couple's past. In 2013, Faith applied for a personal protection order. In the report, she wrote:
"He is trying to make me leave our home. We're filing for divorce. He's being belligerent, kicking things. He kicked the couch while the baby was sleeping on it. He's just kicking things, threatening me and saying if I don't leave, things are going to get ugly. He jumped at me like he was going to attack. This went on for four hours."
That request for a protection order was denied due to what WDIV reported as "insufficient allegations."
One neighbour hinted at such abuse, as well. Michelle Carson said Green was kind to the kids but not his wife.
"He kept her confined," Michelle Carson told WDIV. "[She] couldn't socialise, like a prisoner."
Wayne County prosecutor Kym Worthy also blamed domestic violence.
According to WWXY, she said:
"There is nothing that better illustrates the silence of violence than this case. A confluence of events led to the deaths of four beautiful children. The alleged evidence in this case will show an appalling level of domestic violence that was cataclysmic. We must push the issue of domestic violence back to the forefront and be constantly educated about it."
But much of the Dearborn Heights community seemed shocked.
The older teenagers' father, Chadney Allen, Sr., was caught completely off-guard.
"They didn't give me any red flags," he told WXYZ.
"It just shows you never know what's going on behind closed doors," one neighbor told WDIV. "It's sad. It's a horrible thing that happened."
"Nothing we can do about it, just keep them in our prayers and do the best for the mother," said another. "I really feel bad for the mom. You know, I'd rather die if my four children were dead."
"They were just quiet, you know, kids seemed always happy. The guy seemed really good, too," Terry Strickland, another neighbour, told WWJ. "I mean, the time when he accidentally hit my car, he was polite, he came and knocked on my door and told me what happened and we worked things out. He seemed like a very good guy."
Dearborn Heights Mayor Dan Paletko said, "It's a very well-kept house. There's no reason that you would ordinarily think that there's something unusual. Nice pool, extra yard, the house is landscaped nicely. It looks like a nice home that a family was living in."
Since the slayings, the community has reached out in various ways, according to WXYZ. A memorial of flowers and teddy bears has appeared on the home's front steps and continues to grow. The Pye Funeral Home donated caskets to the family. Finally, a vigil for the family members was held Thursday night.