Biden and Harris respond to attacks from Trump campaign

Sen. Kamala Harris said during an ABC interview broadcast Sunday that President Trump called her "nasty" as a distraction, and Joe Biden also addressed Trump's attacks on him.

Details: In the interview Sunday evening with ABC's David Muir, Biden said of Trump questioning his mental fitness to lead: "Watch me."

• Addressing Trump calling her "nasty," "a madwoman" and more, Harris said, "There is so much more about what comes out of Donald Trump's mouth that is designed to distract the American people from what he is doing every day that is about neglect, negligence and harm to the American people."

Of note: If elected, Biden would be the oldest president sworn into office at the age of 78. Biden's mental fitness has previously been questioned whenever he stuttered, but he has previously said stuttering isn't to blame for his verbal mishaps.

Go deeper: Other key moments from Harris and Biden's first joint interview