A mother of 11 who battled two types of cancer in her 49 years died Sunday in the mass shooting at Pulse nightclub in Orlando, Florida.

>> Read more coverage of the Orlando nightclub shooting stories

Brenda Marquez McCool was visiting Pulse with her son and niece when shots rang out Sunday, the Advocate reported. Both her relatives were able to escape from the nightclub.

Around 12 a.m., just hours before Omar Mateen fired 202 rounds into Pulse, McCool posted a video of people dancing at the club.

She said goodbye to her children Saturday night, said McCool's oldest son, Farrell Marshall, on a GoFundMe page he set up to support his family. Three hours later, they got word that she had been struck by a pair of bullets.

She was later pronounced dead.

"One decision changed the lives of many," Marshall wrote.

A Brooklyn native, McCool raised her seven boys and four girls on her own for the most part, according to her son. She lived in California for 15 years, but spent much of the time after that moving around the country.

"My mom was a single mother at certain times in our lives and it was hard staying in one place," Marshall wrote. "We moved a lot."

Mike Marquez, another of McCool's sons, told WNEP his mother would often visit Pulse to dance with her son, Isaiah Henderson, 21.

"According to Henderson, McCool saw the gunman coming closer and shooting, so she pushed her son out of the way so he could run for the door," the TV station reported.

"She's a hero," Marquez told WNEP.

Remembrances flooded social media on Monday and Tuesday, including a message from New York Mayor Bill de Blasio.

"I want my mother to be remembered as a great person, a person who loved you no matter what color, no matter what ethnicity, no matter what sexual orientation," Marquez told WNEP. "I want her to be remembered as a loving and caring person."