UPDATED: 2/17/2016, 10:20 PM

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KAUFMAN COUNTY (CBSDFW.COM) – A Kaufman County woman and her boyfriend are in jail, accused of waterboarding her special-needs son and tying his genitals up with rope as a form of punishment.

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Christi Howell, 40, and Casey Shackleford, 45, are also accused of beating the boy, who is younger than 14 and mentally disabled, according to an affidavit.

The boy told authorities that he was punished for telling Shackleford that he had “put his finger inside the family dog’s butt,” according to an arrest affidavit.

The affidavit said Shackleford grabbed the boy, and held a towel over his face, while Howell poured cold water over his mouth and nose.

The two also tied rope around the boy’s genitals and neck, causing cuts and burn marks, according to the affidavit.

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The boy also accused Howell of beating him for failing to maintain good form while doing push-ups. He said he was struck 20 to 30 times on the back, buttocks and elbows.

They said Howell admitted that she had poured water on the boy and tied a rope to him, but she said the abuse was Shackleford’s idea.

An arrest warrant had been issued for Shackleford, who turned himself in to Kaufman County authorities late Wednesday.

Howell’s bail is set at $250,000.  No word yet on bail for Shackleford or the exact charges he will face.

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KRLD’s Austin York and CBS 11’s Jeff Paul contributed to this report.