In a grim layering of American tragedies, a 67-year-old man with a lung disease was able to crowdfund his medical treatment only after his wife died in the Santa Fe, Tex., school shooting.

Cynthia Tisdale, 63, a substitute teacher at Santa Fe High School, was among the victims in Friday’s shooting, in which a student used a shotgun and a handgun to kill eight students and two teachers.

She had hoped to one day retire and be a “full-time grandmother,” said John Tisdale, her brother-in-law. “It will never happen.”

Her husband, William Tisdale, was diagnosed with idiopathic pulmonary fibrosis, which leads to scarring of the lungs, making it harder to breathe. He was denied a lung transplant in December, when he was told he had 12 to 18 months to live, according to the family’s GoFundMe page. Ms. Tisdale had taken the substitute teaching job partly to help pay his medical bills.