Sylvester Stallone secretly agreed a multi-million deal with his late half-sister amid claims he had abused her for years.The 'Rocky' star agreed 16 years ago to give Toni-Ann Filiti $2 million plus $16,666.66 per month for her lifetime, as well as a trust with $50,000 per year for psychiatric and medical expenses. According to the papers - which have been seen by the New York Post newspaper - Filiti ''asserted claims for personal injury, including physical injury'' against Stallone, who ''vigorously denied and continues to deny and dispute all claims of wrongdoing''. Sources say Filiti - who died last August at the age of 48 - threatened a lawsuit, but the 66-year-old star settled before it was ever filed. Stallone's mother, Jacqueline, says the settlement was the result of a ''shakedown'' and Stallone was a victim of blackmail. She said: ''This was nothing more than a shakedown. Toni-Ann was on 65 Oxycontin pills a day, and she threatened Sylvester. A drug addict will do anything. When Sylvester became famous, she didn't have to hook. He was trying to help her. He caved in. ''There were too many conflicting stories. At the time [in 1987] he was very hot, and his lawyers said, 'Give her something just to shut her up.' '' But Filiti's 19-year-old son Edd, hit back saying: ''They've made my mother out to be the black sheep,'' and claims Filiti told him of the abuse allegations by ''screaming about [them] over and over'' while in a Florida hospital bed last year. A Stallone representative said: ''Unfortunately, celebrities, politicians and athletes frequently find themselves the targets of blackmail efforts by family members and associates who fabricate claims in order to extort payments from them.''