William, 67, was diagnosed with idiopathic pulmonary fibrosis, a degenerative condition that scars the lungs and eventually closes them off to oxygen flow, causing the patient to become progressively frail.
Life expectancy is about five years for the condition. Doctors gave William up to 18 months in December, but he was still denied a lung transplant, his son wrote.
William's health had already been in decline for years. But Cynthia was always there for them in the small town of Dickinson, Texas.
"She has cared for my father every day of their lives," Recie wrote in a statement provided to the Washington Post, even as she recently became a substitute teacher at Santa Fe High School.
Recie believed he found a long shot, last ditch effort: Experimental and unproven stem-cell treatment in Dallas.
He launched a GoFundMe campaign on March 29, in the name of his father, to pay for what insurance could not.
"With the procedure I have a chance for more time with your momma (my wife of 47 years), my children, and my wonderful grandchildren who I so much want to see grow up as much as possible," William wrote to Recie, according to the funding campaign page. "I fear without this I won't make it to see 2019."
Such stem-cell treatments have exploded nationwide in recent years, but they are not scientifically proven. Federal regulators have not approved such treatments, and many sceptics call the clinics offering them snake-oil salesmen preying on desperate patients.
Researchers say that although there are promising signs that stem cells may one day be used to treat intractable conditions and diseases, they are still years away from developing effective and proven therapies in most cases.
And yet, the Tisdales placed their hopes in the fundraising campaign, hoping to watch it roll toward a goal of US$13,000 for the treatment.
Instead, it was a crawl. Just US$1213 came in just over seven weeks, GoFundMe said, a modest draw that would supplement Cynthia's moonlighting job. She worked at night as a server at a local restaurant to help cover medical costs, the Monitor reported.
Meanwhile, William's condition deteriorated.
Then, a student entered the high school where Cynthia was assisting an art teacher, carrying a .38 revolver and a shotgun. Cynthia never walked out of the school.
Recie, a detective in nearby League City, arrived to identify the body.
Stories of Cynthia's dedication to her family and William's terminal condition went viral, and in that amplification, the campaign flourished.
In an update, Recie wrote the loss was unbearable for his father, but the alert pings announcing donations gave him some comfort.
By yesterday, the family recognised that the pathway to treatment was being built by strangers across the world who were horrified by Cynthia's death. With more than US$50,000 raised as of today, the family's funeral cost and bills are covered, Recie wrote.
"We are still in such disbelief that anything good can come out of such a horrific event . . . my mum always made good come out of bad situations though and this is no different for her," he wrote on the campaign page.
And in a surprising twist, the funds may even be enough to opt for a lung transplant, he added.
Donations have come from nearly all 50 states and 22 countries, GoFundMe spokeswoman Kate Cichy told the Post today. Before the killings, donors had contributed from just six states, she said.
The family has said had differing opinions on why Cynthia took the substitute teaching job after two decades of paralegal work. Her brother-in-law John Tisdale said she took on both jobs to help boost income, the Monitor reported.
But Recie told the Post she took the job because it was her nature to help others. "She didn't have to do it. She did it because she loved it," he said.
Recie and his father William could not be reached for comment for this story.
But in an earlier brief call with the Post, William Tisdale offered his thoughts on his wife.
"She was a good woman," he said. "She watched out for me."