Elon Musk's four-year-old son X Æ A-12, who he shares with Grimes, almost caused havoc during his dad's speech at Donald Trump's pre-inauguration rally.

Elon Musk's son X AE A-12 made a surprise appearance at Donald Trump's pre-inauguration rally, and it's safe to say he stole the show in more ways than one.

Little X AE A-12 made an unexpected appearance at the rally just hours before the US President-elect's inauguration.

The rally in downtown Washington on the day before Trump's inauguration ceremony will also feature Hulk Hogan, Kid Rock and Village People.

Elon Musk is expected to speak at a Make America Great Again Victory Rally in Washington, D.C. He previously has delivered remarks at other President-elect Donald Trump events, including a campaign rally at Madison Square Garden.

President-elect Trump is poised to take office on Monday, and some are already wondering whether his policies surrounding electric vehicles will help or hurt automakers including Tesla. The Austin-based automaker has collected a whopping $11 billion from the sale of regulatory credits to other automakers attempting to comply with emissions targets.