Sgt. Eric M. Houck had been expected to return from Afghanistan in less than two months.

But family members on Monday prepared for the Baltimore native’s coffin to arrive at Dover Air Force Base in Delaware, grieving their loss after the 25-year-old was killed Saturday in eastern Afghanistan.

“He is my best friend,” said his sister, Jessica Houck, 22, of Baltimore. “Always there for me. He was and is my protector — someone everyone should look up to. I love him with all of my heart.”

Houck was killed along with Sgt. William M. Bays, 29, of Barstow, Calif., and Cpl. Dillon C. Baldridge, 22, of Youngsville, N.C. The three soldiers were gunned down in an apparent insider attack by an Afghan soldier, according to Afghan authorities and U.S. officials.

All three belonged to the 101st Airborne Division, and the incident, which happened in Nangahar province, is under investigation, authorities said.

Sgt. Eric M. Houck, 25, of Baltimore, with daughter, Violet Houck, 3. Sgt. Houck died in Afghanistan Saturday from wounds suffered in an attack in Nangahar province. (Family photo)

Houck joined the Army in May 2013 and deployed last fall as a forward observer, according to a statement from Fort Campbell in Kentucky, where he had been stationed since 2016.

Family members said Houck, who went to Perry Hall High School before he enlisted, was married to his teenage sweetheart, Samantha.

The pair met when Houck was 15 and she was 14, and they had two children: Eric “EJ” Houck Jr., 5, and Violet Houck, 3.

“It was still a storybook romance, and they were just crazy about each other and their kids,” said his grandfather, Bob Houck.

“Soar High Baby, I love you Eric Houck with all I got,” his wife posted Monday on Facebook.

“You are and will always be mine!!!”

Bob Houck said his grandson was a good and respectful man who played by the rules and was a hard worker, attaining the rank of sergeant in less than three years.

Houck posthumously earned the Bronze Star Medal, Purple Heart, Combat Action Badge and Army Commendation Medal with a second oak leaf cluster for his end-of-tour awards.

Maryland Gov. Larry Hogan (R) said in a statement on Facebook that American and Maryland flags will fly at half-staff when Houck is laid to rest, “in honor of his memory and selfless dedication to our state and our nation.”

“Our hearts are filled with sorrow today as we learn of the passing of Sgt. Eric M. Houck, a native of Baltimore, who made the ultimate sacrifice while serving our country in Afghanistan,” Hogan wrote Monday. “Our sincere prayers go to his wife, Samantha, their children, and all of their family and loved ones in this time of grief.”

Bob Houck added that his grandson could have had a bright future, and that “you never really appreciate the sacrifice these kids make until it happens to you.”

Thomas Gibbons-Neff, Clarence Williams and Josh Hicks contributed to this report.