Former United States president Donald Trump's eldest granddaughter, Kai Trump, took centre stage at the Republican National Convention (RNC) stage on Wednesday as she entered the political arena.

Kai, 17, is the eldest daughter of Donald Jr, the oldest son of the former president, and his ex-wife, Vanessa.

She followed in the foot steps of her parents, uncles and aunts as she she appeared on stage to deliver a short but personal testament to her 78-year-old grandfather who beamed throughout her speech, NPR reported.

Donald Jr introduced his eldest daughter on the RNC stage and said that it was her "first time ever on a stage" and "first time ever giving a speech”.

Kai took centre stage and introduced herself to the crowd as "the granddaughter of Donald Trump", before starting her speech.

She said: "I'm speaking today to share the side of my grandpa that people don't often see.

"To me, he's just a normal grandpa. He gives us candy and soda when our parents aren't looking. He always wants to know how we're doing in school."

She continued: "Even when he's going through all these court cases, he always asks me how I'm doing. He always encourages me to push myself to be the most successful person I can be.

"Obviously, he sets the bar pretty high, but who knows, maybe one day I'll catch him."

She added: "A lot of people have put my grandpa through hell... and he’s still standing."

Earlier, after the recent assassination attempt against Trump, Kai also offered words of support for her grandfather on social media.

She posted a photo of a bloodied Trump raising his fist in the air moments after the shooting. She captioned the Instagram post: "We love you Grandpa. Never stop fighting!"