Robin Williams' widow claims she doesn't have enough money to cover her mortgage.

Susan Schneider, who was married to the late actor for three years before he committed suicide at their home in Tiburon, California last August, has filed new court documents, claiming she can no longer afford to live in the $6 million waterfront property.

Robin left instructions saying Susan, 51, should be allowed to live in the house until her death and receive enough money to maintain it through her lifetime, but she is unhappy with the inheritance sum his estate came up with, according to legal paperwork obtained by gossip website TMZ.com

She also claims she hasn't received any money for the house since Robin died because no one can agree on the amount.

But the 'Mrs Doubtfire' star's children, Zelda, Zak and Cody, believe their stepmother is unfairly seeking a ''guaranteed income stream'' and allege she wants to deplete their inheritance.

Their lawyers asked a judge to dismiss her petition in court last Friday (14.08.15).

While they have agreed to let Susan continue living in the house, they claim she is holding on to precious family heirlooms and memorabilia that their father left them in a bid to secure more money from his estate.

According to additional court documents, obtained by the New York Daily News, their lawyers argued: ''The petitioner has refused to accept the Trustees' final determinations and has unlawfully retained possession of categories of personal property belonging to the Williams children.

''Petitioner is seeking to increase her share of the trust assets at the expense of the Williams children.''