(CNN) Cynthia Tisdale spent the last years of her life working two jobs to help pay for the medical expenses of her husband, who suffers from a life-threatening lung disease.

Now it appears the death of the beloved substitute teacher in the Santa Fe High School shooting may lead to him getting the medical treatment that could save his life.

Tisdale's husband, William, suffers from idiopathic pulmonary fibrosis , a life-threatening disease that causes scarring in the lungs. It leads to breathing difficulties and a shortage of oxygen in the brain and other organs. And sufferers can only expect a life expectancy of up to five years after diagnosis.

His family set up a GoFundMe page in late March to raise the money for a stem cell treatment. Funds came in slowly at first but soared over the weekend as people learned more about Tisdale and her devotion to her husband.

By Monday morning, the campaign had already exceeded its $30,000 goal -- enough to pay for the stem cell treatment and possibly (with a second opinion) get a lung transplant.

"We are still in such disbelief that anything good can come out of such a horrific event," the family said. "My mom always made good come out of bad situations though and this is no different for her."

Giving her husband a second chance at life

Tisdale was considered something of a saint by her family and friends in Pharr, Texas. The mother of four children was described as kind and generous by those who went to church with her at Anchor Bible Baptist Church in Pharr.

But her greatest act of kindness and love was toward her husband, William.

She worked as a substitute teacher during the day and as server at a local restaurant at night to help pay for his medical expenses, her brother-in-law John told The Monitor newspaper.

"Since my brother has been very ill the last couple of years, she was a very excellent caregiver and she worked two jobs for extra income to help," the brother-in-law said. "She worked at the school and a second job as a server at night at an Italian restaurant chain."

Tisdale's husband was diagnosed with the disease back in December and was told he had at most about a year and half to live. His doctor told him he wasn't a good candidate for a lung transplant, Tisdale's family said, so lung stem cell treatment may be his only shot at prolonging his life.

And with the money that's coming in to the GoFundMe page , that's now a possibility.

"We don't know how to put it all into words but thank you doesn't give it enough justification. We (reached) the goal for funeral costs, bills, and possible lung transplant with second (doctor) that we never thought was an option," the family wrote.

Her son, a detective, ID'd her body

Tisdale was one of 10 people killed when a gunman, armed with a shotgun and a .38-caliber handgun, opened fire at Santa Fe High School soon after classes started on Friday morning.

It was Tisdale's own son, a detective who responded to the shooting scene, who had to identify her body and notify other family members of her death, The Monitor reported.

The shooting suspect, 17-year-old Dimitrios Pagourtzis, was arrested and charged with capital murder and aggravated assault on a public servant.

Her family said William Tisdale is devastated by the loss of his wife yet cognizant of the fact that even in death, she is still helping him.

"It was hard for him to fight before and now losing my mom has made it unbearable," the family wrote on the GoFundMe page, "but every little notification on his phone gives him a chance at something."