After several weeks of strict professional military training, Pfc. Katelyn Castro and Pvt. Rhys Bullington completed their transformation from civilian to Soldier.On Jan. 16, the two Soldiers endured a grueling final trial of Basic Combat Training called the Night Infiltration Course -- a 200-meter low crawl beneath barbed wire performed under heavy machine gun fire. As trainees maneuvered in near-pitch-black conditions, tracer rounds and flares intermittently lit up the night sky and simulated explosions rocked the air.The NIC, which comes after four days and nights in the field, and at the end of the final phase of training -- the Forge -- is a turning point for many trainees, said Capt. Maria Kienle, Castro's company commander."You see a huge transformation from day zero when they're civilians just wearing the uniform to week eight when they finish the Forge," she said. "You see it in the discipline."The official U.S. Army patch, which Castro and Bullington now wear in Advanced Individual Training, was awarded to them in a special ceremony following the NIC, where trainees are called into formation around a massive bonfire and recite the Army Values.According to BCT cadre, the ceremony serves as a rite of passage and represents the exact moment trainees become Soldiers."At that moment, honestly, I felt overwhelmed, just emotional, because I finally graduated basic (training)," Bullington said. "I was very happy, and it kind of made me enthralled being able to get that patch finally and call myself a Soldier."However, Castro said she felt differently, and that she let go of things which made her a civilian before that night."For me, the patch ceremony is supposed to be you becoming a Soldier, but I feel like everybody has that one day of basic (training) where they break down," she said. "There's that day where you're like, 'I'm in the military. This is real, I'm in the Army.'"She said reality struck her one day in training while she fought off sleep and pulled security all night in the woods."I took everything a lot more seriously. At first, I was like, 'This is fun,' but now I'm (thinking), 'This is real. We're actually going to have to do this one day.'"For Bullington, the intensity of the NIC left a resounding impression."The very heavy and wet sand was really when it kicked in," he said. "Right as soon as you start crawling and you get closer to the wire above your head, bullets start spraying above your head and you hear explosions from your left and right. The sand gets more and more thick; it feels like you're (going) into quicksand. You start sinking in, and then, you start getting even more and more wet, you get heavier and heavier, and every time you try and take that extra inch, it feels like you're weighing a ton."Because combat medics' AIT is located in San Antonio, Texas, Castro's unit held a graduation ceremony Jan. 30 at Baker Theater. Her family again drove 15 hours from their home in South Carolina to attend."Kaitlyn has always been the type to push and to achieve what she wants to achieve," Castro's mother, Sonya, said. "We'd go to the ends of the Earth for this."Bullington, however, did not depart Fort Leonard Wood. Combat engineers remain here for the training specific to their military occupational specialty.According to Staff Sgt. Douglas Wellman, one of Bullington's drill sergeants, the Soldiers are currently learning how to use breaching explosives and construct bridges."(In AIT), our teamwork is even more of a lifeline," Bullington said. "If one of us messes up with explosives or carrying this heavy equipment, it could mean something like losing a limb or losing your life."Just days after first arriving on Fort Leonard Wood, Castro said she hoped to leave with the proper mindset of a Soldier.At her graduation, she said she considered that mission accomplished."I think I've changed morale-wise," she said. "The people next to you are your brothers and sisters, and it's like their lives are just as important to me now as mine is."