A legal expert told Fox News Digital that Cassie Ventura's mother Regina may prove to be a crucial witness in the federal case against Sean "Diddy" Combs.

R&B singer Cassie finished testifying in the Sean “Diddy” Combs sex trafficking trial Friday after four emotional days on the witness stand during which she was questioned about the deepest, most disturbing secrets of her sex life and described being beaten and raped by a man she once loved.

Multiple witnesses in Sean "Diddy" Combs' sweeping federal sex-crimes trial testified on years of alleged physical, sexual and emotional abuse.

Dawn Richard was called to testify against Sean “Diddy” Combs in his sex trafficking trial. The Danity Kane/ Diddy-Dirty Money alum told the jury that she witnessed Combs hit his then-girlfriend Cassie with a skillet full of eggs at his Los Angeles home in 2009.

Dawn Richard testified in Sean “Diddy” Combs' trial, detailing witnessing violent abuse against Cassie, Combs' former girlfriend. Richard recounted a 2009 incident where Combs allegedly struck Cassie and threatened Richard's life if she spoke out.

Sean 'Diddy' Combs' trial continued as his ex-girlfriend Cassie testified about alleged assault and accusations of abuse

Dawn Richard, famed for her time with with the girl's group Danity Kane, is expected to further corroborate Cassie's testimony against Sean Diddy

Cassie Ventura testified against Sean "Diddy" Combs in a federal trial, detailing alleged abuse and her role as a star witness in the sex crimes case.