Sumter, SC (WLTX) - A family in Sumter has been without their father and husband, who’s been serving overseas for over a year, but on Wednesday they got a surprise they won't ever forget.

Part of the sacrifice that our men and women make serving in the armed forces is being away from their families. That means missing out on watching your kids play sports, learn in school and just to watch them grow.

When you're away from family for a long period of time, Master Sgt. Steven Zimmerman knows it can feel like forever.

"It's been tough. I just got back from a year remote tour to Korea. Just excited to be back and see the family," Zimmerman said.

The U.S. Air Force Crew Chief says keeping his family in mind helps him get through the long periods of time without them.

"The whole reason you're doing the job. Something to come back home to. That alone is one of the biggest parts of it. It'll keep you going," he explained.

While Zimmerman has already reunited with his wife Melisa and son Gavyn, his youngest son Karson has been in class at Ebenezer Middle School.

While he thinks he’s working on another class assignment, he has no idea who’s about walk through the classroom door.

After the emotional reunion between a father and his son, Karson says he couldn’t believe it.

“I was just like wow, I didn't expect it. It’s been tough having to go places and having someone else take me or my brother to our games without our mom being at one of our games. She can only go with one of us,” Karson said.

No matter what they're doing, they're just happy they can do it all together as a family. Steven says seeing his son was something else.

"It was awesome," he said. "Just really happy. It's a great day. At this age, they're changing so much. School work, sports, just growing, learning. That's the roughest part of it but just glad to be back."

The kids say the first thing they’re wanting to do is play video games together at home on their PS4.