'Next American president has the heart of a lion', says Trump Junior on his father

Milwaukee: Donald Trump Junior has asserted that his father's instinct in the face of an assassination attempt has shown the world that the "next American president has the heart of a lion".

Addressing the Republican Party's once-in-four-year convention here on Wednesday night, Trump Jr, said that the assassination attempt on his father on Saturday "once seemed unimaginable became a terrifying reality."

Trump, 78, survived an assassination attempt at a campaign rally on Saturday in Pennsylvania, injuring his right ear. The shooting left one spectator dead and two others critically injured. The 20-year-old male attacker was also shot and killed by a member of the Secret Service.

"They say you can't truly know how you'll respond in a moment of danger until you're actually confronted with it," the 46-year-old eldest child of the former president, said.

"So what was my father's instinct, as his life was on the line? Not to cower, not to surrender, but to show for all the world to see that the next American president has the heart of a lion," he said, a day ahead of Donald Trump's acceptance speech as the Republican Party's nominee in the November 5 presidential election.

He said the world saw a spirit that could "never be broken".

"In that moment, my father didn’t just show his character, he showed America’s character when he stood up with blood on his face and the flag at his back. The world saw a spirit that could never be broken," Trump Jr, a businessman said.

He said the US came "millimetres away" from one of its darkest moments.

"A brave firefighter died, others were injured, and as those bullets rained down, we came millimetres away from one of the darkest moments in our nation's history," he said.

He said after the assassination attempt, the Republican presidential candidate "may have moved to the ground, but he stood back up." "And when he did, my father raised his fist into the air. He looked out at the crowd, and what did he say?" he asked the audience.

"We will fight, we will fight, we will fight with our voices," Trump Jr said, adding that they will fight with their votes in November.

The Republican convention on Monday nominated Trump as the party's presidential nominee against incumbent Democratic President Joe Biden.

Trump's eldest granddaughter Kai Madison Trump also spoke at the convention in support of her grandfather.

In her first public speech, the 17-year-old promised to "share the side of my grandpa that people don’t often see."

"To me, he’s just a normal grandpa. He gets us candy and soda when our parents aren't looking," she said.

She described Trump bragging when she had made the honour roll at school and peppering her with questions about her golf game.

Trump's wife, Melania, his daughter Ivanka Trump, son-in-law Jared Kushner and other family members are expected to attend the convention on Thursday in a rare show of public support for the former president as he accepts the party's nomination for the president's post, CNN reported, citing sources.