He died protecting them, said Rob Scott, an Ohio attorney retained by the families of McQuinn and his girlfriend, Samantha Yowler. Scott confirmed McQuinn's death to The Associated Press. He was 27.
"As both families mourn the loss of Matt, they ask for everyone to give them distance and time," Scott said in a statement. "Again, the families thank everyone for their love, prayers and ask that we respect their families' wishes."
Yowler was recovering from surgery after she was shot in the knee at the theater. Her 32-year-old brother, Nick Yowler, who also shielded his sister, was not injured.
McQuinn and Yowler moved to Colorado from Ohio last fall. A Colorado co-worker told the Springfield News-Sun that McQuinn and Samantha Yowler worked with her at Target.
"They're really fun people," said Melissa Downen. "We always go out together."
Micayla Medek loved a night out with her friends, and she was with a group of about 10 of them at the "Dark Knight Rises" premiere.
Medek was "Cayla" to her family and friends. She was 23 years old and juggling classes at Aurora Community College with a job at a Subway sandwich shop, said her aunt Jenny Zakovich, 57, of South Milwaukee, Wis.
"She didn't know what she wanted to do," Zakovich said. "I think her plans were to finish community college and go into a better paying job — probably in the computer field."
An ardent Green Bay Packers fan, Medek, who lived in the Denver suburb of Westminster, would plan her schedule around watching Packers games with her sister and father.
"It was probably just like going to church every Sunday," Zakovich said.
Zakovich said she was planning to look for tickets to a Packers game so her brother could surprise Medek and her sister.
Medek was an independent-minded and sweet girl who rarely asked her family for anything, Zakovich said.
"She was one who wouldn't hurt anybody. She was a very loving person. This shouldn't have happened to somebody like her."
The youngest of the victims killed in the attack was Veronica Moser-Sullivan.
She had just learned to swim, and at age 6, she was a "great little girl, excited about life," her great-aunt Annie Dalton said. "She should be at 6 years old."
Her mother, Ashley Moser, remains hospitalized with gunshot wounds to her neck and abdomen. She has been in and out of consciousness and asking for her daughter during moments of lucidity.
"Nobody can tell her about it," Dalton said. "She is in critical condition, but all she's asking about is her daughter."
Alex Sullivan's family called him "their real life super hero," and he was at "The Dark Knight Rises" premiere celebrating his 27th birthday and his first wedding anniversary.
"Alex was a gentle giant, known and loved by so many. He always had a glowing smile on his face and he made friends with everyone. Alex enjoyed all sorts of movies, was an avid comic book geek and loved the New York Mets," the family said in a statement.
Sullivan had a warm smile and an innocence that endeared him to people, said Shelly Fradkin, whose son Brian was good friends with Sullivan.
She sat next to a makeshift memorial Friday near the theater where an oversized birthday card with a photo of a smiling Sullivan was displayed.
"He's amazing. He was just a big teddy bear. Great hugs," she said.
She said Sullivan was such a big movie fan that he took jobs at theaters just to see movies.
Fradkin and her son spent an "excruciating" day trying to find Sullivan before learning of his death, she said.
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