ven as Kimi Antonelli may be world champion-elect, it is sometimes hard to equate the young man who has driven with such exceptional skill and no little verve to touching distance of an historic first Formula One title with the smiling, wide-eyed kid with tousled hair who still almost looks out of place in the F1 paddock. Yet what has become clear in this extraordinary season is that Antonelli's talent and his personable, endearing character are inextricably entwined.

Whether the Italian seals his place as F1's youngest world champion, at 20 years old, at this Sunday's US Grand Prix in Austin or the next round in Mexico or even beyond that is moot – that he will do so is all but assured and for all that he is still in only his second season in the sport, a more rounded, well-liked champion than the Mercedes driver would be hard to find.

Engage with Antonelli and it is almost impossible not to still see the three-year-old child who insisted on taking to his father Marco's knee to try out the racing simulator the former driver had brought home. Marco would control the pedals and his son the wheel with an irrepressible enthusiasm that could barely be contained and is still there in every dart, feint and incisive pass he makes today.

Pictures from his childhood in Bologna, a couple of hours' drive from where his father runs a racing team in San Marino, show whenever Antonelli has a wheel in his hands there is a smile on his face and his eyes alight. His joy is clear and it is a passion that has run clearly through his career. From going karting at the age of five, a meteoric rise through the ranks, being taken on as a Mercedes junior driver aged 12, then making his debut for the team in 2025 after a whirlwind of three years moving from F4, to Formula Regional and then F2.

The faith Mercedes placed in him, not least in that he was stepping into the shoes of the departing seven-time champion Lewis Hamilton, was huge, yet the team principal Toto Wolff had no doubts as to his talent and his character.

"In the past, there was the opinion in F1 that in order to be winning, you need to be an asshole, you need to be ruthless and opportunistic," he observed this season as Antonelli made a stunning start with five wins on the trot and the entire world was paying attention to the kid who, for many, had come from nowhere. "I don't think that Kimi is that. It's just down to driving faster than the others, and being a nice person also." It is an opinion often echoed by those close to the young Italian. Gwen Lagrue, the talent scout who led Mercedes' junior driver programme, remembers more than just his remarkable talent from their early encounters.

"With Kimi, I saw almost from day one that I was dealing with a different kid," Lagrue said. "First, what impressed me, well, amazed me, was his natural presence. He was already having such an impact on everyone in the paddock, you noticed this kid has something different than the others. Everyone liked Kimi, everyone was hugging him. He was like the Kimi you see today when he was 11. He was so passionate about what he was doing, about racing, about F1, everything."

At the heart of this engaging character it seems is a grounded and emotionally rich relationship with his family. While he was supported in following his racing dreams, he was told unequivocally that if he was to kart on a weekend, school must follow on a Monday until he graduated. He duly did so, completing his school exams just after coming third – his first podium – at the Canadian GP last year.

"Which driver has done the A-levels or the baccalaureate? Name me one that has finished school. No one," Wolff observed pointedly of his prodigy. The role of his family has clearly been crucial. His father as guide, mentor and, both have admitted, stern taskmaster at times, whom Antonelli has described as his "rock". But there is also clearly a hugely important relationship with his mother, Veronica, and younger sister Maggie.

"My dad is always going to give me his point of view, he's going to give me advice and then if I decide to listen, good, but if I don't decide to listen, it's OK as well," he said. "We always have a strong relationship but this is the same with my mum and my sister. The way I am I don't think I could cope with having a bad relationship with my family member, it's something that I would really struggle to cope with, that's why I couldn't see myself, you know, just taking distance from them."

Intriguingly, racing was not a direction his father had initially wanted him to go in. Marco had been a quick sportscar driver and almost signed as works driver for two German touring car teams but was unlucky in not getting a shot. "I was scared that my son [would] relive the same situation," he said. "At the beginning, I was very stressed about the passion my son had for motorsport."

However, having decided to let him pursue the dream, Marco has been there ever since. He is at the track on many weekends and clearly the pair share an easy, close bond with echoes of the one Hamilton shared with his father, Anthony, in his early years. In Hungary, the race after he had risked receiving a penalty for exceeding track limits on his way to a brilliant win in Belgium, Antonelli laughingly recalled his father's reaction: "He said: 'Congrats, but …' Always a but … 'If I see you doing another track limit for nothing, I'm gonna stretch your neck like a chicken.'"

Antonelli's boyish honesty has been as engaging as his talent. Wolff has noted his ability to switch into a "race mode", a zone where he is wholly focused on the task, where he has a daring, aggressive driving style, pushing to the limit and past it, on occasion, but which he always learns from. "We had to teach him instead of always being at 110%, just be at 100%," Lagrue said which, as Wolff has remarked, is a trait he would rather indulge than having to "take a stick to a donkey".

Yet alongside that verve Antonelli has shown a maturity beyond his years belied by his character when out of the "zone". He has displayed the judgment of a veteran while being able to manage the endless adjustments of touch and feel of the car and its balance – especially of these fiendishly complex modern rides – such that he, like many of the greats, has made it look easy.

Watching him do so this season has been a pleasure not least because he is a driver who has taken such untrammelled and infectious joy in doing so. A feeling perhaps summed up by his father, who told La Gazzetta dello Sport just after his son turned 20: "I hope he remains who he is, sweet and generous, and continues to do what he loves for as long as possible."

Before his extraordinary victory from 19th on the grid at the Italian GP, Antonelli said he wanted to win the championship but that it was important for him to do so by being himself. The latter he can consider a job most admirably well done. The former is only a matter of time.