Stranger scrawls 'UR not handicapped' on mum's car as she took disabled son to see Santa

A mother has been left devastated after a vicious message was scrawled across her car window as she took her terminally ill son to see Santa.

Nancy Coyne and her seven-year-old son Garrett headed to King of Prussia shopping centre in Philadelphia, US.

But their festive activities quickly turned sour after discovering the note in red lipstick that read, "UR NOT Handicap" on the window.

Garrett suffers from the rare condition Batten disease which has left him blind and is causing his motor skills rapidly deteriorate. The condition normally results in childhood death.

"I can’t believe someone could be so obnoxious and ignorant and rude about a situation that I struggle with daily," Ms Coyne told WTXF.

The mother had parked her car in a disabled spot and had Garrett's legal parking card displayed on the dashboard but that didn't deter the unknown culprit making their remark.

"[I was] trying to make memories for my family then this happened," she said.

The devastated family, who have set up a foundation for their son to help with his condition, wish the perpetrator now understands their wrongdoing.

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"I just want the person to realise what they did was wrong and to learn from it and not to it again," Garrett's father, Joe Coyne, said.

A police investigation is underway into the incident with assistance from the shopping centre.

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