Former President George H.W. Bush sent his regrets to President-elect Donald Trump last week after deciding to skip the upcoming inauguration based on the advice of his doctor.

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"My doctor says if I sit outside in January, it will likely put me six feet under," the 41st president wrote in the letter, dated Jan. 10. "Same for Barbara. So I guess we're stuck in Texas."

Bush, 92, was hospitalized Saturday after showing up at Houston Methodist Hospital with "shortness of breath," spokesman Jim McGrath said.

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Bush "responded very well to treatments," McGrath said on Wednesday morning. "(We) hope to have him out soon."

Bush's son, former president George W. Bush, and his daughter-in-law, Laura, will attend Friday's festivities.

"They are pleased to be able to witness the peaceful transfer of power – a hallmark of American democracy – and swearing-in of President Trump and Vice President (Mike) Pence," George W. Bush's office said in a statement.

A spokesman told Politico that neither George W. Bush nor his wife voted for Trump in November. Instead, they voted for "None Of The Above for President," the spokesman said.