MARINE CORPS BASE CAMP LEJEUNE, N.C. -- Four times before had they solemnly gathered like they did today. Now, dressed in fresh, green uniforms instead of soiled, desert tan, and standing atop wine-red-colored carpeting in place of the earthen floors they’d known months ago in Iraq, the warriors of 1st Battalion, 6th Marine Regiment and 2nd Combat Engineer Battalion once again united to commemorate the passing of their brothers-in-arms.On Dec. 2, hundreds of Marines, sailors and four families from across the nation gathered inside the base’s Main Protestant Chapel and held a memorial service honoring their friends and relatives, Lance Corporals Mario ‘Happy’ Castillo, Andrew Kilpela, Joshua Klinger, and corpsman ‘Doc’ Aaron Kent. All four service members were killed by improvised explosive devices during their battalion’s tour of duty in Northern Fallujah from March through October.Chaplain Richard Ryan, 1st Battalion, 6th Marine Regiment’s chaplain, began the service by delivering an invocation, after which the Marines spoke of their friends.“I remember when I first came into 2nd CEB, ‘Happy’ literally welcomed me with open arms,” stated Lance Cpl. Bryan Smith, one of Castillo’s fellow combat engineers. “Mario was the happiest, most positive person I’d ever met. Marines like Mario Castillo are the reason our nation is so great.”Corporal Allen Ryals spoke after Smith to honor Kilpela, another one of their fellow engineers.“Any time I needed someone to talk to, he (Kilpela) was always there for me,” Ryals stated. “I keep his pictures close, his friendship in mind, and his laughter heard by telling his stories and jokes. Through that, he continues to live in me.”Castillo, a Brownwood, Texas native, and Kilpela, a Fowlerville, Mich. native, were both killed June 10 while their unit had been posting signs warning the local populace to beware of insurgent-emplaced IEDs in the area.After the engineers had spoken, Staff Sgt. Michael Beagle took the podium and spoke about the fallen corpsman, Kent.“All the men that knew him knew that ‘Doc’ had a comic voice about him,” stated Beagle, Kent’s platoon sergeant. “Marines would go up to him saying, ‘Doc, my leg is broken in three different places,’ and he’d say, ‘Here’s some Motrin. It’s gonna be alright.’”“In Iraq, he would take all the stress on Marines’ minds and heal it,” Beagle continued. “I’m always going to remember his blue eyes and easy-going voice. He was one of the best corpsmen I’ve ever worked with.”Kent was a native of Portland, Ore., and was killed April 23 after his vehicle struck a roadside bomb outside Fallujah.First Lieutenant Adam Sacchetti, Klinger’s platoon commander, followed after and addressed the audience to speak about his Marine.“Lance Corporal Klinger was a Marine with an undeniable devotion to his family and his fellow Marines,” Sacchetti explained. “I never saw him without his trademark smirk or without something positive to say. He sacrificed everything to protect those he loved.”Klinger, an Easton, Penn. native, was killed June 14 when an IED detonated beside his foot patrol.Ryan and 1st Battalion, 6th Marine Regiment’s commander, Lt. Col. William Jurney, then encouraged the fallen service members’ families to remember the rich legacy their sons, brothers and husbands had left behind.The ceremony concluded with role call, during which each of the fallen troops’ names were called, only to be answered by silence. The bugle melody of taps resonated through the chapel as the attendees filed out. Their eyes lingered on the black-and-white portrait sketches and gear displays of their friends and loved ones, an occasional hand tapping the helmet atop the unused rifle’s butt stock.