With more than half a billion dollars to her name, money is no object for Mariah Carey.

So it may come as a shock to hear the star allegedly won't help her estranged sister Alison, an HIV-positive former prostitute and mother-of-two who has now been left with no choice but to beg her famous sibling for help.

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Alison, 53, claims she hasn’t heard from Mariah in four years. At that time, she spoke with her superstar sister to coordinate a time for Mimi to visit her niece and nephew, Alison’s now 15-year-old son and 13-year-old daughter. The children were hurt and confused when their aunt suddenly cut off ties without explanation.

alison carey mug shot

Alison Carey in her 2005 mug shot. Photo courtesy of Splash.

In fact, she says her children are the only reason she’s willing to stoop low enough to publicly ask her sister for assistance.

“Decisions I’ve made in my life have hurt my children… We don’t have enough food. I haven’t been able to pay the rent this month,” she laments. “I can’t buy my daughter, who’s on her school’s honors list, the clothes she needs — not wants, needs.”

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She fears she’s going to end up living on the streets with her two children and doesn’t know where else to turn, as even her church’s outreach program has been unable to provide her with food or funds.

Mariah and Alison have had their differences, but the older sister hopes they can put that behind them.

alison carey

Alison Carey in 2005, following an arrest for prostitution. Photo courtesy of Splash.

“There’s been a lot of water under the bridge. I’ve done things that were wrong. She’s done things that were wrong,” she says. “But I’ve reached out to her many, many times through the years in every way I could think of to try and ask her for her forgiveness and see if we could start over. We are the only sisters each of us will ever have.”

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Despite what her critics may say, Alison insists she wants more than a hand out from her sister — she wants a second chance.

“I don’t want Mariah to think I only want her for her money, like everyone else does,” she tells ‘’Star’ magazine. “I want her to love me again. I want her to be my sister again.