During his first deployment to Iraq, as a Marine Corps reservist, David Stewart called his wife, Kristine. He said he was thinking about becoming an active-duty Marine.

“I was like, ‘Do it.’ I could just tell how much he loved the Marine Corps,” his wife said. She said his dedication never wavered through four more deployments. While on his fifth, Staff Sgt. David H. Stewart, 34, was killed in Afghanistan on Friday, along with two other Marines.

The son of a lieutenant colonel, Stewart was born in New Orleans and moved wherever his father was stationed, including two tours in Okinawa, his wife said. But he considered Stafford — where the family settled after Stewart’s father retired and when Stewart was in middle school — his home.

There he met Kristine, when they were middle schoolers. They began dating as juniors in high school.

The two married and have a daughter, Mackenzie, 2, and son, Marshall, 14 months.

Marine Staff Sgt. David H. Stewart was the son of a lieutenant colonel. (AP)

“He was the most joyous father you could ever know,” Kristine Stewart said. “He had such a sparkle in his eyes when he looked at his beautiful children.”

She said that she helped her husband decide to follow in his father’s and brother’s footsteps by joining the Marine Corps Forces Reserve. “It was all about serving something that was bigger than ourselves and doing the right thing. I fell in love with him when I was 16 years old because he was like that as a teen, and he just carried that on,” she said.

Stewart deployed to Iraq from September 2004 to March 2005, from March to October 2006 and from September 2007 to April 2008. Then he went to Afghanistan from October 2012 to April 2013. He left for his last deployment this past April, according to the Defense Department.

He served in the 2nd Combat Engineer Battalion (Forward), Marine Expeditionary Brigade Afghanistan, Regional Command Southwest. His wife said that as a combat engineer, he worked on clearing roads during his last deployment.

The Defense Department said Stewart died as a result of a hostile incident in Helmand province. Lance Cpl. Brandon J. Garabrant, 19, of Peterborough, N.H., and Lance Cpl. Adam R. Wolff, 25, of Cedar Rapids, Iowa, also were killed. All three were based at Camp Lejeune in North Carolina.

“He just had so much fun. Gosh, he would come home with this light in his eyes,” Kristine Stewart said of her husband’s early days in the reserves, before September 11, before the wars in Afghanistan and Iraq.

Even after he went to war, five times over, Stewart remained upbeat. “He just was so proud to be a Marine and so proud to serve his country, and I was just so proud of him,” his wife said.

Jennifer Jenkins contributed to this report.