A special Christmas concert at the Copernicus Center in Chicago also included a surprise homecoming for the family of a Marine.Cpl. Zack Mucha hadn't been home for over two years, so he wanted to make his return something that nobody would ever forget. During the concert, Zack`s father was called up to the stage the hold the America flag. He had no idea that he was about to become the center of attention. As 'I'll Be Home for Christmas' played, Zack walked out on stage to greet his unsuspecting dad.As the song ended and the crowd cheered, the men embraced. 'It's the best gift you could give,' Zack's dad said when he finally composed himself.Zack's surprise appearance was arranged by the musical host of the show and a local senior home in Round Lake where Zack is from.