Leighton Meester has sued her mother, Constance Meester, for misusing a monthly allowance that Leighton paid to her for the care of her brother Lex, reports TMZ.
Leighton, 25, has been sending Constance $7,500 every month because Lex has severe medical issues and Constance doesn't work.
In her lawsuit, the Gossip Girl star alleges that Constance misused the allowance for her cosmetic procedures and other personal expenses. Constance also tried to extort money from Leighton, telling her daughter that there was an oral contract between them under which Leighton was required to pay her $10,000 every month for life.
Leighton denies there is any oral contract, but Constance has threatened to sue for $3 million.
In her legal filing, Leighton has asked the court to declare there is no oral contract.
Constance has a criminal record; at the time of Leighton's birth she was in federal prison for her association with a drug ring that smuggled marijuana from Jamaica to the United States.
Leighton spent the first three months of her life in a halfway house to which Constance was transferred to facilitate nursing. Later, Constance returned to prison to serve her residual sentence and Leighton's grandmother cared for her.
In the past, Leighton has maintained that her parents are good people who brought her up well.