Two children got an extra special surprise from Santa delivered to their grandparents' doorstep last Friday.

Andrew, 7, and Abby Durrer, 4, raced to the front door after the bell rang to find a huge, nearly 7-foot-tall wrapped present waiting outside for them.

Clutching the note he received from Santa the night before telling him he would be receiving an early present from Santa, Andrew began un-wrapping the large box only to find his dad, Staff Sergeant Josh Durrer, popping out from inside.

"Oh, it was so precious, absolutely precious," the children's grandmother, Maureen Rehak, told ABCNews.com. "The kids did not know he was going to come home mid-tour for the holidays. We didn't want to tell them because it's just too hard to have Dad coming and going, so we just didn't tell them at all."

Jenn Durrer, Josh's wife, had known since October that her husband would be returning home for the holidays, but she didn't want to tell the children in case there was a change of plans.

"My mom and I were sitting around, and we knew Josh would be arriving late Thursday night. I said, 'O.K., the kids will stay at your house.' We wanted to make sure it was a surprise," Jenn said. "My kids are just at the age where they love Christmas, and I really wanted to involve Santa."

So Jenn's father wrote a note to Andrew, from Santa Claus, explaining he did well in school this semester and listened to his mother while his father was away. Therefore, there would be an extra-special surprise waiting for him the very next day.

"Andrew had the death grip on that Santa note. When he walked out, he peeked around the corner to see if Santa was still there," Jenn said.

But although Santa was long gone, heading back to the North Pole in his sleigh, his father was right there in front of him. The best Christmas surprise he could have asked for, delivered all the way from Korea, where Josh had been deployed on his most recent tour.

"It was fun for the kids," said Jenn. "And Andrew's got a renewed Christmas spirit. He thinks Santa Claus is just the biggest Christmas hero. He went back to school and was telling all the kids how Santa delivered his daddy to him for the holidays."

And this Christmas in particular has a very special meaning to the family.

"It's our first American Christmas. Both our kids were born overseas. It's our first time being home, and it's just neat that Josh was able to be home for our first time."

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