John Legend with his wife, Chrissy Teigen. Picture: Pascal Le Segretain/Getty Images

Hours ago, the son of the Republican presidential candidate took to Twitter to complain about protesters who derailed his father’s rally in Chicago, which was called off due to safety concerns.

“Ha 5 students when asked why they were protesting couldn’t even answer. The participation medal/micro aggression generation is pretty sad!” tweeted Trump Jr, a successful businessman and executive vice president at The Trump Organisation.

Donald Trump Jr with his father, billionaire businessman and Republican presidential candidate Donald Trump. Picture: Ethan Miller/Getty Images/AFPSource:AFP

But Legend, presumably not a Trump supporter, was having none of that.

The All of Me singer and soon-to-be father fired back at Trump Jr, tweeting: “I think they were protesting your racist father. This isn’t complicated.”

Trump Jr replied: “Here we go again. That can’t be the answer for everything you don’t like. That’s why the country is so divided now!”

And when another Twitter user criticised Legend for having “no education”, Legend took aim at him, too — with the perfect response.

“The Donalds and I graduated from the same University, funny enough,” he said.

Yep — Donald Trump, Donald Trump Jr and John Legend all studied at the University of Pennsylvania.

Other Trump supporters on Twitter turned on Legend for his anti-Trump comments, but the singer had the perfect response to them, too.

He tweeted a link to story by The Daily Beast about claims staff at Trump properties would mark black people’s applications with a “C” for “coloured”, as well as other racial codes.

“Yes, Trump trolls. I’m the real racist,” Legend said.

The heated exchange comes months after Legend’s wife, supermodel Chrissy Teigen, became embroiled in a Twitter war of her own with Donald Trump himself.

In December, after Trump tweeted about a forthcoming meeting with black pastors that he said was strictly not a press event, Teigen replied: “So don’t tweet about it, you tw*t.”

When a Trump supporter told Teigen she “can’t hold a candle to (Trump’s wife) Melania Trump when it comes to beauty and eloquence”, Teigen shot back: “LOL poor Melania doesn’t need to be dragged into this. She goes through enough already.”