CHICAGO (STMW) — A Cook County judge Tuesday found a Lakeview woman accused of suffocating her eight-month-old son while battling a severe postpartum condition not guilty by reason of insanity.

Janet Thies-Keogh is a “very, very sick” woman, Judge James Linn said, adding that Colin Keogh died because of his mother’s deteriorating mental health.

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After Linn cleared Thies-Keogh, 32, of murder, she hugged several relatives, including her husband who called 911 after she told him over the phone that “it’s too late” on the night of Feb. 7, 2011.

During the nearly three-hour bench trial, assistant state’s attorney Christa Bowden argued that Thies-Keogh planned to kill the baby and had been waiting for the moment to act when her husband stepped out for a quick jaunt to the gym.

But even the prosecution’s witness, Chicago Police Sgt. Matt Kennedy, sensed that Thies-Keogh was not well when he arrived at the couple’s apartment, in the 3900 block of North Ashland Avenue.

Thies-Keogh had a “grayish” tone to her face when Kennedy said she let him into her unit and he saw the lifeless baby at the foot of the bed in the master bedroom.

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“She was staring off in to space,” Kennedy testified.

Thies-Keogh, who has been receiving psychiatric care and taking medication while out on bond, was most likely psychotic when Colin was harmed, mental health professionals testified.

Thies-Keogh’s attorney Thomas Brandstrader said she was “detached from reality” at the time and “does not even remember” what she did to Colin.

Linn commended Thies-Keogh’s “extremely conscientious” husband for going to authorities as soon as he heard the baby was in danger and said he shouldn’t shoulder blame for briefly leaving Colin in his ill wife’s care.

Linn ordered Thies-Keogh to undergo an evaluation by the Illinois Department of Human Services.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2012. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)