Lisa Bonder Kerkorian, who was married briefly to the MGM mogul, said she faked a DNA test to show her daughter was Kerkorian's.
She now says the biological father is Hollywood movie producer Stephen Bing.
Kira Kerkorian is now 12, and court papers have said that she has known for quite some time that she has "two papas." Kerkorian, 93, has had joint custody of the girl, who lives with her mother.
The settlement, which provides $100,000 a month until Kira turns 19 or until she graduates from high school, no longer is a full-time student or no longer is living with her mother full-time. After that, the settlement says, the child support will be reduced to $50,000 a month.
The agreement also provides for Kerkorian to pay expenses including school costs, equestrian expense, clothing, housing, travel, hobbies, automobile, food, beauty treatments, tutoring, entertainment, parties and pets.
Bonder Kerkorian, 45, a former tennis pro, was married to Kerkorian for 28 days in 1999. They had been romantically linked for years. Kerkorian, once the majority shareholder of what is now MGM Resorts International, is the legal father of the child because the couple married.
The legal battle over child support between Kerkorian and his ex-wife has been going on since 2002. Bonder Kerkorian originally sought $320,000 a month in alimony and child support. The current agreement includes no alimony.
The Associated Press contributed to this report.