Sergeant David R. Jenkins, a satellite communications operator with 9th Communications Battalion, I Marine Expeditionary Force, receives an autograph from Herschel Walker March 24, 2015, aboard Marine Corps Base Camp Pendleton, Calif. Walker discussed the importance of seeking help for mental illness and substance abuse with Marines. He now provides emotional and motivational support to service members, veterans and military families by conducting public speaking engagements at military installations nationwide.