Baltimore Police arrested the relative they said helped 9-year-old Tristan King evade detectives and federal agents for nearly six months after the formerly-missing boy ran from a caseworker.

Denise Day, Tristan’s great aunt, was arrested Wednesday evening in the Brooklyn neighborhood, Baltimore Police spokesperson Lindsey Eldridge said. Day, 60, is charged with abduction of a child under age 16 by a relative and with harboring a child, according to a police news release.

Police said Day “confessed to harboring her 9-year-old nephew and assisting him in eluding officials for more than five months” during an interview with missing person detectives.

Authorities found Tristan at a home in Curtis Bay on March 13, two days after The Banner published an extensive report examining the systemic failures that left him unaccounted for. Authorities got an anonymous tip to go to a house on Filbert Street. When police arrived that morning, they found him asleep in a bed with Day, according to court records.

He’d been missing since Sept. 24.

Tristan is now in what’s called a treatment foster home, which is for children who have a “serious emotional, behavioral, medical, or psychological condition” and require extra supervision and therapeutic care, according to state policy.

On the day he was found, Baltimore Police and Mayor Brandon Scott’s office said criminal charges could be pending for “individuals who may have helped conceal Tristan or obstruct law enforcement.”

Day’s criminal case is the latest turn in the saga of tragedies and mishaps that has been Tristan’s life this past year. Last May, his grandmother, Tristan’s legal guardian and Day’s sister, had a stroke that landed her in a nursing home.

Day became his de facto caregiver. In July, their house burned down and they became homeless. Family friends said they lived in a tent in the alley behind their burned home. They said Day, who has a drug addiction, was using fentanyl.

Repeatedly, the systems meant to care for and protect Tristan failed.

Tristan’s school unenrolled the then-second grader in May after he missed more than 10 consecutive days.

Messages of concern for Tristan’s well-being sent to Maryland Department of Human Services workers often went unacknowledged. When the agency briefly took physical custody of Tristan after his great aunt gave him up, he jumped out of his caseworker’s car.

After Tristan went missing in September, Baltimore Police took months to interview people close to him. At one point, the department mistakenly closed his missing persons case.

All the while, community members, Tristan’s relatives and authorities believed Tristan was with Day.

Donna White, Tristan’s grandmother, said in December she thought her sister “ought to be in jail” for keeping Tristan on the streets.

This is a developing story.

Banner photojournalist Jessica Gallagher contributed to this story.