Leighton Meester, Mom in Legal Battle Over Botox, Brain surgery

star Leighton Meester is in a nasty legal battle with her mom and the ugly details are all coming out in court documents.

In a lawsuit filed last week, Leighton, 25, claims her mother, Constance Meester, is using the $7,500 the actress sends home monthly for cosmetic procedures instead of health care for her youngest brother Alexander, who has medical issues.

According to the suit, Leighton’s mother allegedly refuses to work and is using the money for Botox, plastic surgery and hair extensions.

Yesterday, in response to her daughter’s suit, Constance filed a lawsuit of her own, alleging that Leighton promised her a one-time payment of $30,000, and then $10,000 a month, and hasn’t paid.

As a result, Constance – who was once the manager of Leighton – claims there’s not sufficient funds for Alexander, who recently required brain surgery.

In addition to not receiving the money that she claims she is owed for all she has “sacrificed” in building Leighton’s career, Constance also accuses Leighton of assaulting her in the counter-suit.

“At 2:00 a.m. on December 11, 2010, Leighton intentionally assaulted Constance by throwing her to the ground and repeatedly hitting her with a bottle. Leighton had to be pulled off of Constance by her brother Alexander,” notes the document.

“This whole thing’s been really tough on Leighton,” a source told People. “Her only concern has always been taking care of her brother. Leighton’s really close with her brother and her dad — her parents are divorced. Leighton’s a sweet girl — she cares about work, friends and family.”

via USA Today