Ciara is suing Future for $15 million for defamation. The 30-year-old singer filed a lawsuit against her 32-year-old former fiancé - the father of her 21-month-old son, Future Zahir - accusing him of libel and slander. A source told PEOPLE: "She just wants what's best for her and her baby. She is a really great mom. Baby Future is attached to her and a super smart kid. She's really patient and loving with him." Future - whose real name is Nayvadius DeMun Wilburn - recently took to social media to launch a furious rant against the singer, claiming that she was denying him access to their son. He wrote: "This bitch got control problems... I gotta go through lawyers to see babyfuture...the f**kery for 15k a month. (sic)." After claiming that he pays $15,000 in child support every month, Future went on to insist that he just wants to see his son and has run out of patience. He said: "I jus want babyfuture that's all. I been silent for a year & a half..I ran outta patience "Get ready for this classic. Handling my business staying focus making music surrounded by real love & family (sic)." However, Ciara believes that Future - who has four children with four different women - is slamming her in order to get publicity and is annoyed that she has moved on with Russell Wilson. A source said: "Ciara has said that Future uses the situation to promote his music by staying in the press using her name. "He is jealous she has moved on and is happy. He is unable to move on and co-parent in a healthy way. Future has told her he hopes she fails in everything she does and that's just being evil."