On the March 19 broadcast of KBS2's 'Yoo Hee Yeol's Sketchbook', Brave Girls had a surprise reunion with some former marines who previously garnered attention for their shocking cover performance of "Rollin'"!

Throughout the girls' stages of "Rollin'" and "We Ride", two audience members dressed in military uniforms seemed to stand out, not just to the girls on stage, but to viewers as well. MC Yoo Hee Yeol revealed that the two soldiers were in fact, specially invited as audience members today because of their past encounter with Brave Girls.

The two former marines, who each revealed that they had been discharged from their service duties about a year ago, came to join the Brave Girls on stage for an encore collaboration performance of "Rollin'"! After dancing together, the marines told the Brave Girls, "Since you rose to fame so late, I hope that you all will remain famous for a long time."

Furthermore, MC Yoo Hee Yeol had prepared yet another surprise for the Brave Girls on this episode - a surprise phone call from member Yoojung's mother! As soon as Yoojung heard her mother's voice, she began to swipe tears. Yoojung's mother had warm words to relay to her "four" daughters, as she called out the names of each of the members and said, 

"Congratulations to you all for your success. It must have been so hard for you. But even in your most difficult times, you girls banded together and got through somehow, and I am so proud and full of affection for all of you. I sincerely hope that all of the hardships that you went through will not go to waste, and from now on, I hope there will much more happiness from now on. But there may be times when you run into hardship again. When that time comes, remember that you got through your hardships in the past, and try to encourage your peers and others around you."

Catch some clips of Grave Girls on this week's 'Sketchbook', above and below!