WASHINGTON (AP) — Hillary Clinton spent the morning of her husband’s impeachment visiting Capitol Hill to rally Democrats to his side. Pat Nixon kept assuring reporters her husband wouldn’t quit — right up until he did. Eliza Johnson, frail from tuberculosis, kept watch over her husband during his impeachment while sitting in a room across from his White House office.

Melania Trump, just the fourth first lady forced to grapple with the threat of her husband’s impeachment, is pressing on through the ordeal silently, showing no inclination to speak out publicly on behalf of her spouse.

While her husband recently broke his own record on daily tweets and delivered his longest-ever rally speech as he was being impeached, the first lady has largely held her tongue — with the exception of a sharp tweet scolding a law professor who invoked 13-year-old Barron’s Trump name during an impeachment hearing.

“Like every first lady, she’s sort of trying to forge her own path through this,” said Tammy Vigil, a Boston University communications professor and author of a book about Melania Trump and Michelle Obama. “In this particular case, she doesn’t really have a whole lot of history to look toward.”

Melania Trump has said in the past the president is the one the public needs to hear from since he was the one elected.

And while the president has complained about the “great damage and hurt” the impeachment process has “inflicted upon wonderful and loving members of my family,” the first lady’s spokeswoman rejected the idea that Mrs. Trump has been somehow wounded.

“As always, Mrs. Trump is focused on being a mother and wife, and is busy serving our great nation,” said Stephanie Grisham, her spokeswoman. “She is very strong, and after many years now, has become used to political harassment.”

Trump is only the third U.S. president to be impeached, accused of pressuring Ukraine’s leader to investigate Trump’s political rivals as he withheld security aid approved by Congress. Trump is also accused of obstructing House efforts to investigate the matter.

The president, who insists he did nothing wrong, is unlikely to be removed from office by the Republican-controlled Senate.