*Tripping up the stairs, calling Kamala Harris 'president' and introducing his granddaughter as his late son: Biden's numerous gaffes over the years* * Over the years, President Joe Biden has made numerous gaffes and mix-ups and has even been caught falling * On Friday, he was caught tripping up the stairs as he boarded Air Force One at Joint Base Andrews. * Just one day earlier, on Thursday, he referred to Vice President Kamala Harris as 'President Harris' * Earlier this month, while making a speech, he seemed to forget the name of his Secretary of Defense Lloyd Austin * On Election Day, in November, Biden introduced a crowd to his granddaughter, but referred to her as his son * In 2008, he told then-Missouri state senator Chuck Graham to stand up for the crowd at a rally, before realizing he was in a wheelchair Over the past few years, President Joe Biden has made the news for things he's said and done - but not related to policy. Rather the 78-year-old has had a knack for gaffes. During speeches or while answering questions, Biden is known to make mistakes, have mix-ups or even digress. The commander-in-chief has even been caught tripping a time or two, raising speculation about his physical health. View some of Biden's misspeaks. foot-in-mouth moments and slips. [VIEW THE VIDEOS](https://www.dailymail.co.uk/news/article-9382043/Bidens-numerous-gaffes-years-tripping-stair-calling-Harris-president.html)