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For Moore, Okla., teen, graduation is bittersweet

Like many of her classmates here, Saturday's high school graduation was an emotional ceremony for 18-year-old Alyson Costilla, a moment of  pride long anticipated. NBC's Ron Mott reports.

By Ron Mott, Correspondent, NBC News

MOORE, Okla. – As it was for many of her classmates here, Saturday’s high school graduation was an emotional ceremony for 18-year-old Alyson Costilla, a moment of pride long anticipated.

But unlike most of her peers, she accepted her diploma one day after a final farewell to her mom, Terri Long, one of 24 people killed in Monday’s devastating tornado.

“She talked about how exciting, like how excited she was to see me walk across the stage,” Costilla said, choking back tears. “How excited she was going to be for me to move to college.”

Costilla’s mother was aware ominous weather was headed toward town and authorized the school to allow her daughter to leave early for home.

While waiting there for her mom to arrive -- who, too, had left early from her job at the Federal Aviation Administration to check on Costilla -- the phone rang.

“She called and told me I needed to get out of the house and drive as far south as I could. So, I did,” Costilla said.

Fleeing for safety as the massive tornado churned and roared ever closer, Costilla repeatedly tried reaching her mother.

“She wasn’t answering,” she said. “Eventually got through to her and she told me she was on I-44 and driving toward the house, which I didn’t understand.”

After a few harried minutes, both mom and daughter behind the wheel, they connected again by cell phone.

“She stopped at the 7-Eleven, and we don't know why because it's not on her way home,” Costilla said. “She said she was in the 7-Eleven in a bathroom with a whole bunch of people, and she said she was going to wait it out.”

Terri Long never made it out of the convenience store alive.

For her worried family, it would take an agonizing delay to learn her fate.

“After it happened, my sis called me and told me that 7-Eleven had been hit,” Costilla said. “We were calling all the hospitals and none of them had her.

“You think it would never happen to you, like, mom's strong. She's going to get through it. It’s not going to happen to her.”

Later, Costilla’s uncle identified her mom’s body at the morgue.

When her name was called at the graduation ceremony Saturday—one of three for Moore’s high schools—Costilla’s biggest supporter was missing. In the audience, though, as friends and family cheered her accomplishment, there were large photographs of Terri Long clutched in their hands.

“It's just really hard because I wanted her there, and you can't physically hug her,” Costilla said.

Ever since the unimaginable happened Monday afternoon, however, Costilla’s heart has been engaged in an unbreakable emotional embrace.