Ms. Robinson’s lawsuit asked for at least $12 million, double what her former boss’s lawsuit demanded.

In 2008, Mr. De Niro hired Ms. Robinson, then 25, as his executive assistant at Canal Productions. The company “contracts the services of Robert De Niro to third parties,” according to its suit, and is separate from Tribeca Enterprises, an entertainment company that Mr. De Niro started with others in 2003. At Canal Productions, Ms. Robinson said, she assisted Mr. De Niro on films including “Hands of Stone” and “The Comedian.”

It is common for high-profile celebrities to hire people to handle personal matters, but Ms. Robinson said some of what she was asked to do crossed into inappropriate territory. Several tim es, she said, Mr. De Niro would ask her to scratch his back, sometimes requesting that she do so in a private bathroom adjoining his office.

Ms. Robinson said that several times when they were on the phone together, she could hear him urinating. Once, when he had asked her to purchase a television for his bathroom, Ms. Robinson said he asked her to imagine him sitting on the toilet so that she could figure out a good place for the television. She did not say his behavior ever rose to the level of groping or sexual propositioning.

Her lawsuit alleges gender discrimination, asserting that Mr. De Niro’s treatment of Ms. Robinson, including his name-calling, was gendered and that she was paid less than a male counterpart.

In an audio file of a 2012 voicemail message posted on the website of the law firm representing Ms. Robinson, Mr. De Niro can be heard berating her about a work-related matter, calling her a “spoiled brat” and saying “you’re history,” with an added expletive.