Could Pence assume presidency if Trump is sick? What the 25th Amendment says

Supporters gather outside the White House while U.S. President Donald Trump quarantines for COVID-19 at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)

If President Donald Trump's coronavirus diagnosis makes him too sick to fulfill his role, what happens?

The answer lies in the 25th Amendment of the U.S. Constitution, which states the duties of the presidency could pass to the vice president.

Vice President Mike Pence tested negative for COVID-19 on Friday morning and is in "good health," according to Devin O'Malley, Pence's press secretary.

U.S. President Donald Trump salutes from the steps of Marine One helicopter on the South Lawn of the White House upon his return to Washington from Bedminster, New Jersey on Oct. 1, 2020. (Yuri Gripas/Abaca Press/TNS)

Trump has "mild symptoms of the coronavirus," The New York Times reported Friday.

Should the president's condition worsen, Trump is allowed to sign off on Pence fulfilling his duties, the Constitution states.

"Whenever the president transmits to the President pro tempore of the Senate and the Speaker of the House of Representatives his written declaration that he is unable to discharge the powers and duties of his office, and until he transmits to them a written declaration to the contrary, such powers and duties shall be discharged by the Vice President as Acting President," Section 3 of the 25th Amendment States.

A member of U.S. Secret Service monitors the crowd outside the White House while U.S. President Donald Trump quarantines after testing positive for COVID-19 at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)

The 25th Amendment was first invoked in 1985 by President Ronald Reagan during his second term. George H.W. Bush took over for Reagan when he underwent colon cancer surgery.

"I am about to undergo surgery during which time I will be briefly and temporarily incapable of discharging the Constitutional powers and duties of the Office of the President of the United States," Reagan wrote.

The transfer of power lasted eight hours and Bush reportedly played tennis for most of the time, according to NPR.

An anti-Trump flag flies outside the White House while U.S. President Donald Trump quarantines for COVID-19 at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)

President George W. Bush transferred power to Dick Cheney in 2002 and 2007 when he went under anesthesia for colonoscopies, according to History.com.

"I did so because we're at war and I just want to be super cautious," Bush said, CNN reported in 2002.

White House Chief of Staff Mark Meadows talks to members of the media outside the West Wing of the White House on Oct. 2, 2020 in Washington, D.C.

Supporters gather outside the White House while U.S. President Donald Trump quarantines for COVID-19 at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)

Supporters gather outside the White House while U.S. President Donald Trump quarantines for COVID-19 at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)

Kehinde Ogun from Brooklyn, New York salutes in support of U.S. President Donald Trump during his COVID-19 quarantine at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)

Supporters gather outside the White House while U.S. President Donald Trump quarantines for COVID-19 at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)

A tourist points at the White House while U.S. President Donald Trump quarantines for COVID-19 at the White House in Washington, D.C. on Oct. 2, 2020. (Yuri Gripas/Abaca Press/TNS)