Fairell Tubbs told INSIDE EDITION that Carson has never reached out to her.
Dr Ben Carson's step-sister tells INSIDE EDITION she hasn't met him - and won't be voting for him.
"He never reached out to me," Fairell Tubbs said.
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Her step-father and Carson's father, Robert Solomon Carson, was buried in a rundown suburban Detroit cemetery in an unmarked grave.
A metal marker, No. 75, is all that identifies the Baptist preacher, who died in 1992 from Parkinson’s disease, a neurological disorder.
Ben Carson, who was already a famous neurosurgeon, did not attend his father's funeral in 1992, according to the step-sister. Fairell Tubbs says she looked after the elder Carson until the day he died.
She told INSIDE EDITION: “It was hard because I was his caretaker. I was closest to him. He was a tall, strong man and all of a sudden he withered.”
Ben Carson was eight years old when his father left home. Robert Carson eventually remarried and lived at a home in Detroit.
Strangely, Fairell and Ben have never met. She says her mom, Mary, even invited Ben to their wedding but he didn't come.
"He was an important man at the time," she said. "He didn't have time for that."
She said she recently tried to reach out to her step-brother through his presidential campaign office but says she is still waiting for a reply.
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When asked by INSIDE EDITION if she would vote for him she, she said no.
“I can't vote for him. I am a Democrat. I’m not going to vote for him,” she said.
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