Leighton Meester is involved in a catfight, but it's not in her CW show "Gossip Girl." Instead, it's in the courts.
The actress struck first, filing a lawsuit in Superior Court of Los Angeles on Friday against her mother, Constance Meester, accusing her mom of taking money she sent for her younger brother, who suffers from various illnesses, and using it for cosmetic improvements.
Leighton claims in her suit that she began voluntarily paying for health insurance for her mother and her brother, Lex, and sent Constance around $7,500 a month for her younger sibling's living and other expenses.
According to the actress' suit, she believes her mother "has been using the money... to pay for cosmetic procedures for herself, including plastic surgery on her face and stomach, botox injections for her face, fillers for her hands and hair extensions," the suit reads.
Leighton claims that after she stopped sending money to her mom, Constance began claiming the two had an oral agreement for the actress to support her at a sum of $10,000 a month for the rest of her life.
The "Gossip Girl" star wants a judgment to determine there is no oral agreement, an award of legal fees over this suit and any other monies the court awards.
On Monday, however, the star's mom fired back, filing a countersuit for breach of contract, among other complaints, claiming the actress broke off an oral agreement to pay her an initial sum of $30,000 plus another $10,000 a month plus health insurance, and care for her younger brother's health needs.
Constance claims Lex needs 24 hour care and she is unable to bring in another source of income.
"As a direct result of Leighton's breach," Constance's filing reads, "there are no funds to feed and care for Alexander. No funds are available to pay utilities and the ordinary basic requirements for sustaining life."
She goes on to claim the actress promised to take care of Constance and Alexander, pay for his school and buy them a home.
Constance is seeking an undisclosed amount of damages at a trial.
Copyright 2011 by NBC Universal, Inc. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.