TULSA, Oklahoma - Family members say early onset dementia may have contributed to a west Tulsa murder suicide.

They say a man is suspected of killing his wife before turning the gun on himself. The bodies were discovered around 2 p.m., Tuesday.

The woman's daughter said she knew something like this may happen. Tulsa Police were back out at the same address that they've visited lately for domestic problems. Only this time, they brought the medical examiner and body bags.

"I think there was stress in the family and it had been ongoing," TPD Sgt. Dave Walker said.

The woman's family hadn't heard from her and called police for a welfare check at the house where she lived with her husband.

Inside, police found the 51-year-old Petra Hardeman and her husband, 62-year-old Don Hardeman, shot to death.

Investigators believe the Don Hardeman shot his wife, then killed himself just a few days after a big blowup between the couple.

"I thought, 'Oh no, it's happening again,'" Ernestine Newton said.

Newton works nearby and said, last Friday, the police were at the couple's house, guns drawn and demanding the man come outside.

"They had their bullhorn out and called him outside," she said. "He come out with a bottle of water acting like he didn't know what was going on or anything. Next thing I know, they had him down on the ground and arrested him."

The man was taken away for a mental health checkup.

The woman's daughter said her stepfather was showing signs of dementia lately, and that was leading to violent outbursts and problems in the marriage.

She said she told her mother to leave after Friday's events, but her mom thought she'd be OK, since she's an elderly care nurse and had experience with dementia patients.

"When you're with them, it's different," Newton said. "You can't help them like you can when it's someone else. It's different if you're involved with them."

The woman's daughter agrees, but said her mother's passion was helping others. She said her mom was a loving mother and a wonderful grandmother.

The woman leaves behind four children.