The troll accused the 25-year-old of 'milkin' her former boyfriend's death.
She responded by saying: "I pray you never have to deal with anything like this ever and i'm sending you peace and love."
Later tweeting: "Some of the sh** i read on here makes me sick to my stomach. it scares me the way some people think and i don't like this world a lot of the time. If only we could be more compassionate and gentle with one another. That'd be sick."
Her friend Halsey, 24, had her back though as she took aim at the hater.
She tweeted: "Ari the world could only dream of being as compassionate and gentle as you. And since ur being, as always, so classy and nice, allow me the honor of telling them to shut the f*** up."
Mac Miller died Sept 7, 2018, aged only 26, at his Studio City home from a drugs overdose.
According to the L.A. County Coroner the rapper died from a mixture of fentanyl, cocaine, and alcohol.
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