Pittsburgh, Pennsylvania - A clip of Joe Biden recently went viral, as it shows the president telling a wild tale about one of his long-gone relatives.

On Monday, Biden joined his Vice President Kamala Harris on stage for a campaign rally in Pittsburgh as she garners support from union members as the current Democratic presidential nominee.

Being back in his home state seemed to drum up old memories, as Biden, during his speech, told the crowd about how his great-grandfather, Edward Francis Blewitt, was "the second Catholic elected" to the state's senate.

"I remember they talked about, when [they ran] against him in 1906, they said, 'Guess what? He's a Molly Maguire!'" Biden recalled.

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He went on to explain that his great-grandfather was an Irish Catholic working the mines, and as "A lot of the English owned the coal mines," the two groups would regularly clash.

"But there was a group they called the Molly Maguires," he continued. "If they found out the foreman was taking advantage of an individual, they would literally kill him - not a joke. And they would bring his body up and put him on the doorstep of his family."

The president went on to admit that though his family kind of wanted the rumor to be true, it wasn't, which made them "so damn disappointed."