According to paperwork filed in Los Angeles on Thursday, Grigorieva is accusing her former attorneys, Daniel Horowitz and Ron Litz, of advising her to sign some bad agreements -- like one that prevents her from taking legal action against Gibson without compromising her financial settlement.
In the August 2011 settlement, the Russian singer was awarded $750,000, joint legal custody and a house in Sherman Oaks, Calif. to live in until Lucia -- her 3-year-old daughter with Gibson -- turns 18.
Grigorieva and Gibson went public with their relationship in April 2009, just weeks after Robyn Moore -- his wife of 28 years -- filed for divorce. In May of that year, he confirmed that his girlfriend was pregnant. The pair split in April 2010.
Click through the slideshow below to test your knowledge of 10 other celebrity custody battles.