BONDURANT, Iowa -- "I wish I could have been a fly on the wall to see what caused, how could setting up a birthday party cause such a rampage," said Seth Nicholson, a cousin of Tawni and Chase Nicholson, and nephew of Mark and Charla Nicholson.
Seth says Tawni was visiting her parents' home in Bondurant on Thursday night to help plan a celebration for her brother Chase.
"That's just who she was, she was always helping. She loved being with her mom and being with her family and they were setting up something for Easter and for his 21st birthday," said Seth.
Seth says sometime between 8:30-9 p.m. on Thursday, something went terribly wrong.
"After the crime, he (Chase) went to his friend Josh's house, told him, 'I just killed my family and I want you to have my Xbox account,' After what he did to his family and the way that he did it, it was so horrible, what was on his mind was his Xbox account. That shows you where he’s at mentally," said Seth.
Seth says Chase has been struggling with mental health problems for years.
"A ton of medications. When he was younger he abused animals, which is definitely a prerequisite to something like this. The music he was into, his knife collection that he has in his room, he was into violent things. He would say violent things, he'd kind of have an episode where he'd just get really freaked out and he assaulted his father. He ended up going to jail for that," said Seth.
Chase looked up to Seth and would open up to him.
"He'd tell me some things about some cutting that he was doing. He would hear some voices, they would talk to him. His meds were just not working. He'd pretend to take them, tell his parents that he was taking them but really he wasn't," said Seth.
Chase's mental health condition had gotten so bad his mother Charla recently took an early retirement so she could look after him full time.
"She was getting more and more afraid of what he might do, his symptoms were progressively getting worse. He'd have scars and fresh bleeding wounds. The things that he was saying about how suicidal he was, was starting to scare her."