As if graduating from the prestigious engineering school at Columbia University isn't enough cause for celebration, this grad now has even more to smile about.

Just as Ruby Robinson was walking across the stage on Monday after collecting her diploma, she was completely caught off guard by an unexpected yet familiar face.

"I was just so surprised and really shocked he was there," Ruby, 22, told ABC News. "I was so relieved he was OK."

Her father, U.S. Army Capt. Keith Robinson, had flown 14 hours from Afghanistan to Kuwait to the United States just in time to make it to the ceremony to surprise his daughter on her big day.

"I was just trying to breathe before seeing my little girl," Robinson, who hadn't seen daughter since December, explained. "She was walking across the stage and shaking hands, and once I saw her face she started to cry."

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It was a close call for Robinson, who is on his second tour to Afghanistan, to even make it to the graduation.

"About two weeks before, we came to the conclusion I wasn't able to make it," he said. "Then my commander in Afghanistan, he basically wrote me a memo to allow me to go on leave to help get me through that process."

The reunion couldn't have been more perfectly planned as Ruby now gets to have her father home for two weeks to help her celebrate all her hard-earned accomplishments.

"I expected to email him and maybe send pictures of the graduation, but to be able to celebrate in person, that's so great," said Ruby.

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And as for Robinson, he couldn't more proud of his recent college grad as she now begins to embark on her future working for Amazon in Irvine, California, this coming fall.

"She just is such an inspiration to all our family," the delighted father said. "She worked so hard for this day and it just meant so much to be able to finally hold. To be able to see her come across the stage and be able to hug her, that was kind of a tough moment, but she's a little trooper and pulled herself together. She's my little trooper."