An Auburn man who previously served prison time for assaulting a 2-year-old child in 2012 is now facing a murder charge more than eight years after the boy’s death, authorities announced. 

Steven Stuart, 35, is charged with murder in the death of Jayden Carlson, who died in December 2017 after enduring years of medical complications stemming from injuries sustained during an August 2012 assault, Worcester County District Attorney Joseph D. Early’s office said in a press release.

Stuart was convicted in 2015 of assault and battery on Jayden and sentenced to six to eight years in state prison, prosecutors said. He pleaded guilty before a jury trial began, court records show. 

At the time of the 2012 assault, Stuart was dating Jayden’s biological mother, The Boston Globe reported. 

Jayden was 2 years old when he was critically injured. He suffered “severe, life-altering injuries” and died five years later at 7 years old from medical complications related to the assault, according to Early’s office. 

A Worcester County grand jury returned the murder indictment, and Stuart was arraigned in Worcester Superior Court on June 18. He pleaded not guilty and is being held without bail, court records show. 

Defense attorney Nora Leovich told Boston.com that a not guilty plea is “common” at this stage of the proceedings, but declined to comment further. 

“This case is in the early stages,” Leovich wrote. “Mr. Stuart is innocent until proven guilty.” 

Stuart is scheduled to return to court July 20, records show. 

In a Facebook post Sunday, Deidre Carlson, Jayden’s adoptive mother, said she had “mixed emotions” following the indictment. 

“As a family we are relieved that he is now behind bars and we pray that the court system keeps him there for a very long time,” Carlson wrote. “Please pray for Justice for Jayden.” 

What happened to Jayden Carlson 

According to court documents obtained by the Sentinel & Enterprise that are no longer publicly available, responding officers observed bruising on Jayden’s forehead and above his left ear after the August 2012 incident. The child was unresponsive but breathing and was foaming at the mouth. Court records indicated he could suffer permanent brain damage.

Jayden spent years living with devastating injuries. After the assault, he was placed in a pediatric nursing home in Groton and struggled with walking, speaking, and seeing, the Worcester Telegram & Gazette reported.

His adoptive parents told the newspaper that Jayden also suffered seizures triggered by hearing a man’s voice. Jayden required around-the-clock care, took 20 medications, and frequently developed pneumonia. 

Although Jayden made some progress during his recovery, his brain eventually stopped sending vital signals to his organs, the Telegram reported. 

Jayden died at UMass Memorial Medical Center, according to his obituary.

His obituary described a boy who enjoyed spending time with the Southbridge Fire Department, EMTs, and paramedics and loved to “play” the piano. He lived in Southbridge and was survived by his parents, Todd and Deidre Carlson, and three brothers.