Stephanie then went on to explain how she had embezzled at least $80,000 from her employer over the last three-and-a-half years.
'I know it's a lot and didn't go to anything extravagant. We financed our cars & camper and vacations and furniture were paid by tax returns and house sale. It's just amazing how fast money flies out of the account for bills and other expenses,' the first page of the letter read. 'I've never been able to find a balance – I work more and have to pay more daycare. I work less and don't have enough money.'
Stephanie said she was struggling with how to balance work and taking care of her family and feared she would go to prison when she learned that her job, Southridge Healthcare, was being audited.
Stephanie, who worked as an accounts receivable specialist, said she had sought advice from a lawyer and was told she could spend up to 15 years in prison for grand theft.
According to the letter, she was worried that if she went to prison her husband, a group home manager for Southeastern Behavioral Health in Sioux Falls, would not be able to provide for the family.
'Rob can't take care of the kids alone, let alone provide for them,' she wrote, citing his parenting skills and fiances. 'They'd lose the house and have nothing.'
In another portion of the letter Stephanie wrote about Zachary's behavior issues. She said her seven-year-old son, who was a twin, was a 'beautiful soul' but 'a struggle to deal with'.
'He's better off with his momma in heaven where I can take care of him and be at peace,' she wrote about the second-grader.
The letter also told her parents to make sure her remaining three children - Ashton, 10; Mason, 7; and Madelyn, 1 - know how loved they are.
'The kids will be in pain (and so will you) but it WILL get better! It has to! Do NOT let this pain darken the rest of your life and theirs!' she wrote to her parents. 'Please don't let them know what I've done if possible, or try to explain. I'm not a monster – I just wanted my kids to be cared for and loved.'
She continued: 'I'm sorry for what this does to you guys. You gave us everything – I had the perfect family, house, everything – and I ruined it all. I pray that you can forgive me.'
Detectives said Stephanie came up with her plan roughly two months before that fateful September 26 day.
A few days before the murder-suicide took place, police said she convinced her husband to update their wills to state that if something were to happen to both of them her parents would become trustees, personal representatives and the guardians of their children.
The night before the killings, police said Stephanie dropped her one-year-old daughter off at parents' house saying she and Rob had to work early the next day. The morning of September 26, she took Ashton and Mason to school, leaving Zachary at home.
According to the investigators, Stephanie killed her husband while he was standing at their kitchen counter. Police said Zachary was on the couch wearing headphones and playing a game when he was killed.
After killing Rob and Zachary, police say Stephanie packed up various items she thought her other three children would need, placed them in her van and left the vehicle parked in the driveway of her mother's home, about half-mile away.
Stephanie was seen that morning walking from her parents' house back to her Lennox home. Once she was back at her house, detectives said Stephanie sent her mum a text message telling her to call 911 and not to come to the home.
Within minutes, both police and Stephanie's mom were at the house. Police said she was already dead when they arrived.
Bob Hoover, Rob's father, told Argus Leader that he does not understand why Stephanie had to kill his son and grandson. He said her reasoning that Rob wouldn't be able to take care of the kids because of parenting skills or finances was 'totally incorrect'.
'There are so many people that knew him, and that is what gets us through,' Rob's mother, Deb, added. 'The good memories. The happy stuff that we hold onto.'
Detectives said the other suicide letters Stephanie left were for her remaining three children, her brothers, and for investigators.
Police are still investigating the murder-suicide. Lincoln County Sheriff Dennis Johnson told the outlet that once the audit at Stephanie's workplace closes he hopes both families will be able to 'move on and heal'.
'This audit - I think what that's going to do is pretty much confirm what we already know,' he said.
Rob Hoover, a graduate of Watertown High School, was remembered by friends as a loving father and a 'genuinely great guy'.
'He was always the hard-worker on the team,' Will Frantz previously told the Argus Leader, reflecting on their time doing cross country in high school.
'Rob was always the guy who put the work in and got us going.'
Another classmate, Emily Mitchell, said she reconnected with Rob when she posted about issues she was having with her son. She said Rob thought he could use the skills he had learned at his job with the Southeastern Behavioral Health to help her.
'That was just who he was. Saw someone struggling and if he could help them, he'd try,' she said. 'considering we were never close, that small gesture speaks volumes about his character.'
Where to get help:
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• Depression helpline: 0800 111 757 (available 24/7)
If it is an emergency and you feel like you or someone else is at risk, call 111.
