Leighton Meester Sues Her Mom (UPDATES)

This is a "Gossip Girl" plotline sprung to life, but even juicier: Leighton Meester is suing her mom for, basically, being a deadbeat.

TMZ reports that the actress, otherwise known as Blair Waldorf, has filed a lawsuit against Connie Meester for using money she lent to provide medical attention for her sick brother on plastic surgery, Botox and hair extensions.

According to the filing, Meester sends $7,500 per month to provide for sibling Lex Meester, who has severe medical issues. Meanwhile, Mama Meester allegedly refuses to work and tried to convince her daughter that they'd orally agreed on a monthly payment of $10,000 for life. The actress is asking a judge to declare there was never such a contract.

As Leighton-watchers will recall, Meester was born in jail while her mother was serving time for smuggling drugs from Jamaica.

Yeesh. Perhaps "Gossip Girl" would be less played out -- and more fun to watch -- if writers for the downwardly spiraling CW series ripped a plot from the headlines of Meester's family drama, "Law & Order"-style.

UPDATE: Connie Meester countersued, alleging that Meester repeatedly struck her with a bottle. (Bad press: this is so not what Leighton needs right now when she's trying to establish a movie career, etc.)