Joe Biden gets wife and sister mixed up during Super Tuesday speech

Former vice president Joe Biden celebrated a string of victories on Super Tuesday as the race to challenge Donald Trump moved up a gear.

But it appears the excitement of his achievement may have overwhelmed him.

Addressing a cheering crowd, the Democratic presidential hopeful got a bit muddled during his celebratory speech, mixing up his wife Jill and his sister Valerie as they both stood next to him.

You can see what happens in the video above.

And that wasn't the only distraction Biden had to contend with. A protester attempted to storm the stage and derail his appearance, as you can see in the video below.