A west Tennessee grandmother and grandfather have been indicted in connection to the premediated slaying of their 3-year-old grandson, court documents show.

Amy Brasher, 64, of Saltillo, is charged with first-degree murder and aggravated child abuse in the killing of Carson Brasher, who Hardin County officials said died on Dec. 26.

The woman's husband, Jeff Brasher, was indicted on felony charges of child abuse and child neglect on March 25, Hardin County Circuit Court papers obtained by USA TODAY show.

The couple was arrested on March 26, three months after Carson's death and one day after the case was presented to a Hardin County grand jury, court documents show.

The couple is from Saltillo, a small town in Hardin County on the left bank of the Tennessee River about halfway between Memphis and Nashville.

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Indictment charges grandmother Amy Brasher with premeditated murder

A motive in the killing was not released by authorities.

It was not immediately known how the child died, but WKRN-TV reported court records show Carson was found unresponsive at the couple's home before officials pronounced him dead.

Carson's mother, Kimberly Jones, told the outlet the Brashers had legal custody of her son while she was attending rehabilitation, and said she was told Carson "slipped in the bathtub and hit his head" while in his grandmother's care.

Neal Thompson, the district attorney who represents Hardin County, and Hardin County Sheriff Johnny Alexander, whose agency handled the arrest, did not return phone calls and emails on Monday.

USA TODAY has also reached out to the Hardin County coroner.

According to separate indictments,, Amy Brasher allegedly abused Carson and, with premeditation, killed him while her husband allegedly failed to protect him from abuse and neglect.

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'A bright and adventurous soul'

On Monday, the boy's 27-year-old aunt, Meghan Pigg, told USA TODAY Carson's family was mourning his senseless death.

"He was such a sweet little boy, and anyone who met him instantly fell in love with him," said Pigg, who lives in neighboring McNairy County, southwest of Amy and Jeff Brasher's home. "He was so silly and kept you laughing. That little boy could turn anyone’s bad day around in a second and he brought so much joy to anyone who knew his life in the three short years we had him here."

Carson's favorite show was "Paw Patrol" and his love for outdoor play was "a testament to his curiosity and zest for life," Pigg wrote in a fundraising page she create to help pay for her nephew's headstone,

"With his infectious love and radiant spirit, he brought smiles to everyone's faces," his aunt wrote.

Amy Brasher and Jeff Brasher to be arraigned April 15

Amy Brasher remained jailed Tuesday on $500,000 bond, a Hardin County jail spokesperson told USA TODAY. Her husband posted a $100,000 bond April 1.

Both defendants are slated to be arraigned on their respective charges in court on April 15, the Hardin County assistant district attorney handling their case told USA TODAY.

It was not immediately known whether either defendant had obtained an attorney and neither could be reached as online court records did not list their address or a phone number.

Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at [email protected] and follow her on X @nataliealund.