According to a source familiar with the situation, Ivanka Trump, former President Donald J. Trump’s eldest daughter and one of his top advisers, plans to testify before a House committee investigating the Jan. 6 attack on the Capitol on Tuesday.

According to the evidence gathered by the committee, Ms. Trump was one of several aides who tried to persuade the president to stop the violence, which resulted in the deaths of more than 150 police officers and forced lawmakers and Vice President Mike Pence to flee for their lives.

Her testimony comes just days after her husband, Jared Kushner, a top adviser to Mr. Trump, sat for an interview and provided “valuable” and “helpful” information, according to one member of the panel.

Representative Bennie Thompson, a Democrat from Mississippi and the committee’s chairman, said of Mr. Kushner’s testimony, “There were some things revealed, but we’ll just share that a little later.”

Ms. Trump and Mr. Kushner are two of the Trump White House’s highest-ranking officials who have testified before the committee. Because the panel works in secret, the interviews have been closed to the public.

Since January, when the committee sent her a letter requesting voluntary testimony, Ms. Trump’s lawyers have been in contact with the committee. The committee said it had heard from Keith Kellogg, a retired lieutenant general who served as Mr. Pence’s national security adviser, in a letter dated Jan. 20. According to the letter, Mr. Kellogg described Mr. Trump’s refusal to condemn the violence as the mob engulfed the Capitol, despite White House officials — including Ms. Trump — urging him to do so at least twice.

Mr. Kellogg testified that the president had turned down offers from him, his chief of staff, Mark Meadows, and White House press secretary Kayleigh McEnany. Mr. Kellogg then asked Ms. Trump to step in and help.

Mr. Kellogg testified, “She went back in because Ivanka can be pretty tenacious.”

Mr. Kellogg also testified that he and Ms. Trump witnessed Mr. Trump pressuring Mr. Pence to go along with a plan to throw out electoral votes for Joseph R. Biden Jr. when Congress met to certify the Electoral College results on the morning of Jan. 6. Mr. Pence’s phone call was part of an effort to void the 2020 election and give Mr. Trump a chance to stay in power.

The president had accused Mr. Pence of not being “tough enough” to overturn the election, Mr. Kellogg told the committee. Mr. Kellogg testified that Ms. Trump told him, “Mike Pence is a good man.” The committee has spoken with over 800 witnesses and plans to speak with dozens more. On Monday, Mr. Thompson told reporters that he had issued five more subpoenas that day.

Mr. Thompson stated that a subpoena for Mr. Pence had been ruled out due to “significant information” received from two of his aides, Marc Short and Greg Jacob.

“We’ve been able to validate a lot of the statements attributed to President Trump and the vice president without his specific testimony,” Mr. Thompson said.

“The committee has made no effort to get him in,” he said of Mr. Pence, adding, “We initially thought it would be important, but at this point we know that people broke in and wanted to hang him.” His security detail had to protect him in an undisclosed location in the Capitol, according to what we know. We know who tried to persuade him to change his mind about the count and other issues. So, what exactly do we require?”

Mr. Thompson also hinted that Mr. Trump would most likely be called as a witness by the panel.

Mr. Thompson said, “I don’t know what else we could ask Donald Trump that the public doesn’t already know.”