JOLIET, Ill. (STMW) – A south suburban man, after learning his brother was sleeping with his fiancee, slit the throat of his brother’s cat, prosecutors said.

Sean Mulcahy, 31, of Homer Glen, was sentenced Wednesday to 30 months probation and 150 hours of community service for killing the cat after he discovered the sexual tryst.

Mulcahy pleaded guilty to a felony charge of aggravated animal cruelty in Will County stemming from the Aug. 5 incident.

Prosecutors, who had sought a 180-day jail term for Mulcahy, said he slit his brother’s cat’s throat as revenge for the affair.

Chuck Pelkie, a spokesman for the Will County State’s Attorney’s office, said Mulcahy was “enraged and intoxicated” when he committed the crime in the driveway of the home in Homer Glen that he was sharing at the time with his brother, Ryan Mulcahy.

Ryan Mulcahy reportedly found a pool of blood in the driveway and discovered his cat across the street in a ditch, Pelkie said.

Judge Edward Burmila set as conditions of Sean Mulcahy’s probation no alcohol, no pets and continued psychological treatment, Pelkie said.

Prosecutors had sought jail time based on a prior history that includes a 2002 conviction for criminal damage to property, and a 2009 conviction for reckless driving, Pelkie said. “They were concerned that it showed a violent tendency,” Pelkie said.

Will County State’s Attorney James Glasgow wrote the law that raised animal cruelty from a misdemeanor to a felony, Pelkie noted, adding, “He is serious about prosecuting these cases.”

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