R Kelly [Courtesy]

 One of R Kelly 's alleged 'survivors' claims he told her all about getting his teen bride Aaliyah pregnant.

Lisa Van Allen, who is one of the women featured in documentary Surviving R Kelly, claims Kelly also told her he was sleeping with the late singer's mother.

Kelly - real name Robert Sylvester Kelly - married Aaliyah in 1994 when she was 15 and he was 27.

The marriage certificate stated that she was 18, with Kelly's tour manager Demetrius Smith admitting that he helped forge the documents.

Now, in an interview with Vlad TV, Lisa claims Kelly talked to her about the reasons behind the wedding.

She said: "He told me about him and Aaliyah, their situation, they had a pact, pins and eyeballs.

"No matter what anyone said or if anyone stuck pins in their eyeballs they would never tell about their relationship, things like that.

"He told me that they were married, that she was pregnant, that they did doctor up the marriage certificate so she would say she was 18 so they could get married.

"And the reason they got married was that they felt like if he was married to her and he said he thought she was 18 then he wouldn't be charged if someone found out she was pregnant until they were able to get an abortion and get it annulled."

When her interviewer says he was led to believe that Kelly married Aaliyah because he got her pregnant, Lisa said: "Yep, that's exactly what happened."

"But he did get a little more in-depth with details of when her mother found out and that her mother, he actually stayed at their home in Detroit and her mother was actually sexually attracted to him as well and he said when Aaliyah would go to sleep that he would...

"Now this is what he said, he said he would go in the living room and he and she would do sexual acts on the couch while Aaliyah was asleep in the bedroom."

Lisa also says Kelly opened up to her about suffering sexual abuse at the hands of his sister.

Kelly's brother, Carey, has also spoken out about their older sister, Theresa, claiming she molested them for six years when she was left in charge while their mother was at work.

Kelly is currently facing a string of sex abuse charges, including some against underage girls.

He has denied all allegations and charges brought against him.