Mariah Carey's sister was reportedly arrested for prostitution.

The “Calling for Love” singer's sister, Alison A. Carey, was arrested after an undercover police officer caught her in the act of “soliciting money for sexual favors” at a hotel in Saugerties, New York, according to the Daily Freeman.

Police were tipped off by an online ad posted by Alison. A portion of the ad posted on Backpage, a classified ads site, included lyrics to one of Mariah's songs, “Fantasy.”

“Im a pretty lady looking for guys who are looking to have some fun and get into a world of pleasure that other woman just cant provide two you, woman with the ability to make the earth move for you and to get you to see stars,” the ad reportedly read. “ITS SUCH A SWEET, SWEET FANTASY BABY, WHEN I CLOSE MY EYES I COME AND TAKE YOU ON AND ON. [sic]”

Mariah and Alison have a rocky relationship. Early this year, Alison put out a video asking her sister for assistance for her medical needs. Alison, who was diagnosed as HIV positive, was attacked at her home in April, causing her to have brain damage.

In the video, Alison pleads: “Mariah, I love you, and I desperately need your help. Please don't abandon me like this.”

Morgan, Mariah and Alison's brother, told the Daily Mail that the singer's refusal to help her sister has resulted to the worsening of the latter's mental problems.

“Alison was institutionalized for observation after wandering in the street barefoot and partially dressed, causing the police to be concerned,” Morgan said. “Her behavior was caused as a result of damage done in the attack and her having missed the medications she was taking.”

Representatives for the singer said at that time that Mariah had extended help to her sister and her extended family “for over two decades” and that she had spent “hundreds of thousands of dollars” on Alison and her family.

Mariah has yet to comment on her sister's arrest.

Mariah Carey Mariah Carey's sister was reportedly arrested for prostitution. Pictured: Mariah Carey attends the 27th Annual GLAAD Media Awards at Waldorf Astoria Hotel in New York on May 14, 2016 in New York City. Photo: Getty Images/Dimitrios Kambouris