Hunter Biden suggests Ambien contributed to father's infamous debate

• Then-President Biden's performance against then-GOP nominee Trump exacerbated Democrats' worst fears about his age and capacity to lead.

Driving the news: "I know exactly what happened in that debate," Hunter Biden told YouTube personality Andrew Callaghan.

• "He flew around the world, basically the mileage he could have flown around the world three times. He's 81 years old. He's tired as sh–t," the president's son said.
• "They give him Ambien to be able to sleep. He gets up on the stage, and he looks like he's a deer in the headlights," he added.
• Ambien is prescription sedative used to treat insomnia.

Zoom out: Hunter Biden, who was pardoned by his father for criminal charges in California and Delaware, did a pair of interviews released Monday, marking his first public comments since the election.

• In an episode of "At Our Table with Jaime Harrison," with the former chair of the Democratic National Committee, Biden acknowledged his father had aged during his presidency.

• "We watched Joe Biden turn 80 and 81 and then 82. We watched him get old in front of our eyes," Hunter Biden said. "That does not mean that you're incapacitated."
• He continued, "How can you measure whether someone is incapacitated or not? What you would do is measure them by the standard of whether they're achieving the goals that they set out to do when they took the job."

Go deeper: Biden wanted to testify at Hunter's trial, new book says