Bryan Hetherwick bought a Russian-made Makarov handgun from the personal collection of a gun dealer in Mukilteo, about 25 miles north of Seattle, on the afternoon of Aug. 5, then less than three hours later shot his grandson, Brennan, and then himself, police said.
Police and gun control advocates concede that even if the dealer had been required to run a background check it is not likely he would have found anything that would have prevented him from selling Hetherwick the gun, because the man had never been committed to a mental hospital by court order.
But the man's wife, Carolyn Hetherwick, said she believes the five-day waiting period that is required under Washington state law for handguns sold by dealers, but not by private sellers, would have given her mentally ill husband time for second thoughts.
"Every single weapon must need registration," she told ABC News affiliate KOMO-TV in Seattle.
The Hetherwicks had raised their grandson since he was 10 months old, and like his grandfather, Brennan had been diagnosed as suffering from bipolar disorder.
At the time of the shooting, Bryan Hetherwick was severely depressed from lack of work, health problems, and from dealing with Brennan's issues, his wife said. Knowing his wife's troubles with multiple sclerosis, he'd spoken of suicide in the past, she told KOMO.
"What was the guy thinking when Bryan was so urgent to get this right away?" Carolyn Hetherwick said, referring to the gun dealer.
The man who sold Bryan Hetherwick the gun, Lyman Armey, told The Seattle Post-Intelligencer he saw nothing unusual in the man's behavior, and said there was nothing illegal about the transaction.
"He was never in my gun shop. It was a personal firearm," he told the newspaper. "I didn't do anything illegal but I regret everything about it."
Police agree that in legal terms, the gun dealer did nothing wrong.
"If the particular weapon is from a gun dealer's personal collection and not from his business inventory, there are no checks. That means there is no waiting period," Monroe Police Chief Tim Quenzer told KOMO.
Quenzer said he agrees with Carolyn Hetherwick that the laws need to be changed.
The shootings occurred right outside the Monroe Police Department headquarters. It is not clear why Bryan Hetherwick chose that location, but in an interview with KOMO-TV the day after the tragedy, Carolyn Hetherwick tried to find some explanations for what happened.
She said still couldn't understand how her husband could kill anyone, but she felt she knew what triggered it.
Bryan Hetherwick was depressed and had been suicidal on and off ever since he lost his insurance job to corporate downsizing in Texas last June, she said.
The couple had been hopeful when they moved to Washington earlier this summer, but he still couldn't find a job and he couldn't get health insurance coverage, she said. Even more devastating was the fact he couldn't find help for his grandson, she added.
"He worshipped Brennan," Carolyn Hetherwick said.
Because of his bipolar disorder, Brennan needed special, expensive care, she explained.
"Who else needs help more if you're unemployed, disabled, you can't work and you have a child with special needs?" she asked. "I spent days on the phone just calling all these places and could not get a thing."
The combination of his inability to find work and to get the care his wife and grandson needed seemed to put Bryan Hetherwick in a downward spiral, she said.