Mariah Carey 's sister, Alison, has been arrested for prostitution after she offered to have sex with an undercover policeman. Mariah was devastated when she heard, because she was trying to help her sister to get on with her life after their parents divorced.

A friend told The Mirror: "When Mariah learned of her sister's arrest, she was absolutely devastated.

"She's touring Europe promoting her new single, but finding out that her sister is in trouble once again has made her inconsolable. She can't concentrate on her performances."

A year-and-a-half ago, Alison - who is HIV positive - was arrested in New York as a result of her drug addiction. She was bequeathed over half a million pounds in her father's will to help sort of her life. But it looks like Mariah had enough. She decided to cut the line of help she has been providing her sister.

The friend continued: "Over the years, Mariah has done everything in her power to try and get her sister clean and leading a normal happy life.

She had an open cheque book where her sister's concerned and has always tried to offer her emotional support as well.

He added: "Mariah is looking for Alsion to want to help herself. She can be there with love and support, but at what point do you not enable someone any longer?"