Retired probation officer had mysterious note in her pocket when she killed ex-daughter-in-law, herself on posh UES street: sources

The terminally ill retired probation officer who gunned down her ex-daughter-in-law on the Upper East Side — before killing herself — had a mysterious note in her pocket when she died, sources told The Post.

The note had the words, “For Police” written on it, the source said.

It was found in Kathleen Leigh’s pants after she killed ex-daughter-in-law Marisa Galloway, on East 88th Street Friday morning — a slaying police say was sparked by a bitter custody feud involving Leigh’s granddaughter.

The contents of the note were not immediately clear.

A mother of two, Galloway, 45, had just put her 1-year-old daughter into the backseat of a parked white Honda Civic during an apparent custody switch-off when Leigh shot her in the head and back, cops said.

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Leigh then took her own life. The baby was not harmed in the shooting.

The special education teacher was locked in a custody battle over the 4-year-old girl she shared with Leigh’s son.

Leigh, a 65-year-old retired Cook County, Illinois, probation officer, had been battling terminal cancer and was living with her son on East 79th Street while she received treatment.

Leigh’s daughter declined to comment Saturday when reached by the Post.

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The grandmother frequently complained to neighbors that Galloway was abusing the 4-year-old girl — an image which didn’t fit with descriptions offered by the younger woman’s neighbors of a caring, loving mother.

“She was so wonderful and she loved her kids,” one resident in Galloway’s East 86th Street apartment building told The Post, with tears streaming down her face.

Between July and November 2021, police took five domestic incidents reports involving Galloway and her ex. The father complained in several reports that his daughter came home with bruises, according to sources.

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Two led to Administration for Children’s Services complaints, and were later deemed unfounded, sources said.

The two shared custody after they split, with the father having custody Friday through Monday while Galloway had their daughter the rest of the week, sources said.

Leigh shot Galloway once in the moments after she had loaded her younger daughter and a stroller into the car, fired another shot into her back while Galloway laid on the ground — then shot herself in the head, NYPD Chief of Detectives Joseph Kenny said police observed on security footage.

Galloway was found covered in blood but still breathing, slumped near the car’s rear, while Leigh lay on the ground nearby, witnesses and sources said. Two handguns were recovered.

Leigh was pronounced dead at the scene. Galloway was rushed to Weill Cornell Medical Center, where doctors declared her dead on arrival, Kenny said.

Additional reporting by Georgett Roberts, Dean Balsamini and Georgia Worrell

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