Crystal Harris has no rights to the Playboy mansion.

While the 26-year-old blonde married Playboy founder Hugh Hefner, 86, on New Year's Eve (31.12.12), 18 months after she first called off their wedding, she reportedly signed a pre-nuptial agreement which will protect his assets.

A source told RadarOnline: ''Hef's lawyer dispatched his assistant to the Playboy Mansion approximately three weeks ago with the final version of the prenuptial agreement for them to sign.

''The prenup protects Hugh's Playboy assets, and it also has specific language about the famous Playboy Mansion. If the couple divorces, or if Hef dies, Crystal would have to vacate the mansion, and has no legal rights to the iconic Holmby Hills estate. Hef wanted to sign the prenup at the house so photographers wouldn't spot him going into his lawyer's office.''

Hugh has four adult children from his previous marriages to Mildred Williams (1949 to 1959 ) and Kimberley Conrad (1989 to 2010) and they are expected to inherit his vast estate.

The couple recently rescheduled their wedding just months after Crystal left Hugh shocked when she called off their marriage five days before they were due to wed in June 2011.

Hugh has said he wants to stay with Crystal until he dies and doesn't care about the 60-year age difference between them.

He previously tweeted: ''The dramatic age difference between difference & Crystal & me really doesn't matter. Whatever time I have left, we want to spend together (sic).''