Correction appended, May 28, 2014

The bloodstained floor of his father’s garage is a long way from the Iraq streets where Isaac Sims served two tours of duty in the U.S. Army’s famed 82nd Airborne Division, but it was there that the violence finally caught up with him.

Tortured by symptoms of PTSD, turned away by an overbooked hospital run by the Department of Veterans Affairs—his mother says she pleaded with doctors to let him sleep on the hospital floor—Sims was shot by Kansas City police on Sunday after they answered a neighbor’s 911 call. Police say Sims was firing a gun from inside his parents’ home and was killed when he moved to the garage and leveled the weapon at the SWAT team.

Family members don’t believe that the 23-year-old veteran was a threat to police. “With his sniper training, if he was shooting at them he would’ve hit them,” his sister Shawnda Anderson told TIME. But everyone could agree that the root cause of the confrontation was that Staff Sergeant Sims was falling to pieces, and felt like he had nowhere to turn.

“He was in so much turmoil from seeing so many dead bodies in Iraq,” said Anderson. Patricia Sims, mother of the dead soldier, put it this way: “The last six months have been such a nightmare for him. The V.A. kept saying, ‘we’ll get to you later.’ ”

Officials at the V.A. hospital in Kansas City referred questions about the case to Washington, where a department spokesperson said that the “matter is currently under investigation.” Citing federal privacy laws, the agency declined to discuss any specifics of Sims’s case.

Still, the reality of V.A. overcrowding has been commanding headlines and driving Congressional hearings for weeks, driven by revelations that some hospitals have falsified records to mask long wait times. As the daughter of a Korean War veteran, wife of a Vietnam vet, and mother of a veteran of the Iraq War, Patricia Sims knows a lot about the V.A. system, and she said Tuesday that the Kansas City hospital is “great compared to a lot of places” in the system. “But they’re slow; they’re overbooked; they put him off and they put him off and now he’s dead.”

She spoke as friends and family members moved dazedly around the scene of the young man’s death in eastern Kansas City. The family car was on blocks—disabled by police during the stand off, she said. Meanwhile, a funeral home was refusing to collect the body on behalf of the family without payment up front. Shawnda Anderson said that her parents weren’t even sure they wanted to pay a funeral home: to bury their son would only confirm that he is truly gone.

According to family, Sims lived an itinerate childhood, traveling the country from one trailer park to the next as his father pursued work as an electrician. A gentle, peacemaking sort of boy, he never grew tall (his sister puts him at 5-foot-3, but according to a Facebook post, he preferred to say 5-foot-5). But he was wiry and dogged, and at 17 enlisted in the Army for what he intended to be a career.

(In 2009, Sims recorded a holiday greeting from Iraq. Watch below)

Instead, after six years and two combat tours, he mustered out, suffering from unspecified disabilities. Unmoored, he began abusing drugs—huffing aerosols primarily—and behaving erratically, his mother said. According to one source who had been briefed on his medical history, Sims suffered “nightmares, flashbacks—just massive Post-Traumatic Stress Disorder,” with symptoms easily triggered, yet seemingly impossible for him to discuss.

In April, after pleading guilty to two counts of domestic violence, Sims came under the supervision of Municipal Court Presiding Judge Ardie Bland. Widely admired for his work with troubled veterans, Bland placed Sims on probation through a program jointly run by the court and the V.A. Launched in 2009, the Veterans’ Treatment Court tries to restore veterans to “law abiding, productive lives within the country they have defended,” according to municipal court spokesperson Benita Jones. The probation was to include intensive treatment, random drug testing, and frequent reviews.

Sims was distraught over the conviction, which crushed his hopes of starting a new career as a police officer, his mother said. Increasingly alarmed by her son’s deterioration, she offered to send him with a blanket to the V.A.’s in-patient mental health facility, reckoning that a soldier doesn’t need a bed to sleep in. Instead, the intensive treatment envisioned by the special court failed to materialize in time.

“We are saddened by such a tragic loss,” Judge Bland said in a statement. “Our hearts must now go out to the family of Mr. Sims with our prayers and support. We will continue our efforts in the Veterans’ Treatment Court, in his honor and in honor of the others that have served this country.”

A memorial fund has been established in Sims’ name at the United Credit Union.

According to police: A neighbor reported shots fired from the Sims home shortly after noon on Sunday. The SWAT team fanned out, surrounding the house, and the inhabitants of the 2300 block of Lawndale Avenue were evacuated to safety. Hostage negotiators quickly researched the soldier’s story in hopes of coaxing him out. But “things went rapidly downhill,” in the words of one witness, and in a spatter of gunfire Isaac Sims went down, dead on the battlefield that had consumed his life.

And there was one more fallen soldier to mourn on Memorial Day.

-with reporting by Karen Ball/Kansas City

Correction: An earlier version of this story incorrectly referred to the Department of Veterans Affairs

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