Almost two years later and Llilliam Alonso is still wondering how it could happen.
"There are so many questions unanswered," she told NBC 5 Monday.
How could her elderly father walk out of a hospital alone and no one stop him?
"I don't understand why they didn’t even ask a question," she said.
In August 2016, Severino Alonso was admitted to Swedish Covenant Hospital. He was recovering from a stroke. The 87-year-old had difficulty walking independently.
But on the morning of Sept. 4, Severino’s family says he got dressed then walked out of the hospital. Security video shows him leaving the building with his walker, no questions asked.
"Nobody stopped my father," Llilliam said.
A short time later a good Samaritan found Severino on a sidewalk roughly a mile from the hospital. He’d fallen down and hit his head.
By the time he got to the intensive care unit, he went into a semi coma.
No one knew he was missing for almost three hours.
Severino was taken back to Swedish Covenant where he died nine days later.
"They all failed him, every single one, they all failed him," Jessica Henry, Severino's granddaughter, said.
"He was never checked on, that is what caused it and makes me angry," son-in-law Mike Henry said.
Severino’s family has filed a lawsuit against the hospital. They say their lives will never be the same with him.
"It's negligence on multiple levels: the staff, the security, the policies, lack of policies," attorney Tara Devine said.
Attorneys for the hospital did not immediately respond to request for comment.