Lawrence released an open letter yesterday about the gender pay gap specifically in Hollywood. She mentions not only the pay difference but the reasons why women might stay quite for fear of being called 'bratty' or 'bossy'.
“When the Sony hack happened and I found out how much less I was being paid than the lucky people with dicks, I didn’t get mad at Sony,” she writes. “I got mad at myself. I failed as a negotiator because I gave up early. I didn’t want to keep fighting over millions of dollars that, frankly, due to two franchises, I don’t need.” She writes that a need “to be liked” and the fear of seeming “difficult” or “spoiled” kept her from demanding more money.
http://www.theguardian.com/film/2015/oct/13/jennifer-lawrence-hollywood-gender-pay-gap