College graduation day is a momentous occasion for students already, but when you throw in the extra-special surprise of being handed your diploma by your brother, who is a Marine, whom you haven't seen in about a year and wasn't expecting to be in attendance, that's the icing on the cake.

Kacy Watson, 28, of Norman, Okla., was graduating from Mid-America Christian University May 4, when she was completely caught off guard hearing the presenter announce her brother's name, Staff Sgt. Michael Burkhart.

"They said his name and my heart just exploded, and there was my brother," Watson told GoodMorningAmerica.com. "It was the only thing I wanted."

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Before the ceremony started, the school faculty asked Watson to stand in the very back of the line for the procession because her last name started with a "W." She was confused, but went along with the plan.

"We were all gathered in this big room," she explained. "I think there were 600 of us graduating. I was standing with my friends and one of them said, 'You're W, so you're going to be the end of line marker.' And I was like, 'Oh, but I want to stay with my friends. But they had me stand in the back anyway."

Watson patiently waited for her turn to cross the stage, when the presenter motioned for her to stand next to him.

"I was like, 'Oh, my gosh, I got some kind of award I didn't know about,'" she said.

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Although she wasn't receiving a school award, she actually ended up with something even better. Her brother appeared, with Watson's diploma in hand.

"We were both bawling," she said. "As soon as I grabbed him, I said, 'I can't believe you're here.'"

Watson had not seen her brother since July of the previous year. His commanding officer at Camp Pendleton, Calif., had given him special permission to fly into Oklahoma City the night before her graduation.

Watson's mother managed to keep the whole thing a secret from the entire family.

"It was such a great day," Watson said. "I never expected it. It was awesome. We're a very, very close family and I had been telling him for weeks I wish he could be there, but he couldn't. Nothing could ever top that moment ever."

Watson's twin sister, Lacy, submitted the heartwarming moment to Welcome Home Blog, helping the video go viral with more than 20,000 views.

Staff Sgt. Burkhart left the following Monday for redeployment to Japan.