ST. PETERSBURG, Fla. -- It was 10 years after the death of their father that associates of filmmaker Laura Brownson brought her an article to read about the late Dan Wheldon.
Standing below the monument on Dan Wheldon Way along the downtown St. Petersburg race course that honors the late two-time Indianapolis 500 winner, his two pre-teen sons were named junior development drivers at Andretti Global in their own bid to follow the father they barely knew.
Wheldon was 33 when he was killed in a crash at Las Vegas Motor Speedway just five months after winning his second Indy 500 title. His son, Oliver, was an infant riding in his mother's arms on the victory lap. Sebastian, who has home videos as a toddler with his father, was not yet 3 but kissed the bricks at Indianapolis Motor Speedway alongside the beloved British racer.
Wheldon was a popular, funny, confident character in the IndyCar community and his death rocked the entire series. No one was more devastated than his widow, Susie, who 10 years later was still grieving and yet willing to let her boys follow their father's career path.
Brownson, a mother of two sons herself, in that article immediately found her next project.
"When I read that, I was like, 'OK, this is not a story just about a racecar driver, '" Brownson told The Associated Press. "It's about fulfilling legacy, it's about grief and love and loss and all those universal themes. Sure, it's a story about Dan. But it's a story about Susie and her boys, too."
The result is "The Lionheart" documentary that had screenings at the Tribeca Festival and won awards at the Heartland International Film Festival and the Key West Film Festival. It was shown to an IndyCar-invited audience in St. Petersburg ahead of the season-opening race weekend -- St. Pete was where the Wheldons made their home starting in 2005 -- and makes its wide debut Tuesday night on HBO and streamed on Max.
It's an emotional documentary that leans on archival footage to follow Wheldon's career while interlaying Susie's struggles as a single mother trying to navigate the careers of her sons in a high-risk sport. The film includes private moments with Susie and the boys, who at times find the constant reminiscing "too intense" and express their resentment at being the only racers at the track who don't have a father on hand to help them hone their craft.
Sebastian is now 15 and a moody teenager, while Oliver is a few weeks shy of 13, and Susie packed them up and moved them to Miami so they'd be closer to Homestead-Miami Speedway and near-daily track practice.
Sebastian said he wants to relocate to Europe and climb the ladder system there before returning to the United States to become an IndyCar driver. Oliver also wants to be an IndyCar driver. Both brothers, who are typically sold as a package deal to sponsors, think the Indy 500 is the greatest event in the world and want their chance to win like their dad.
Susie just shrugs about where she's headed next. She's committed to her sons and giving them their chance to follow their father.
"It was never in my mind that I would deny them that, ever," she said. "I knew from an early point that if they ever wanted to do that, I would at least give them the opportunity. I don't want the story to die at the end of Dan's accident."
Sebastian now competes in USF Juniors, a jump up after winning the Skip Barber championship last year. Oliver is now racing in Skip Barber, one year ahead of when Sebastian made the leap, but the multiple-time kart champion scored two podiums earlier this month at Sebring (Fla.) International Speedway.
They acknowledge their father's legacy drew them into racing, but they are determined to make the Wheldon name their own.
"I think it's just part of our family," Oliver said. "I just love it. I love the speed. I love the racing. It's just all we know and love."
And Sebastian said he's long learned to tune-out the expectations on him of being Dan Wheldon's son.
"The pressure comes from just being a racecar driver. It bothered me at one point," Sebastian said. "Like, everybody had an expectation. You stop caring about that."
Brownson said the documentary is much bigger than a racing film and should appeal to a wide audience.
"The story is for people who are drawn to larger themes of sort of familial legacy, love loss, risk taking, all of those things. You don't have to like motor sports to relate to Susie as a parent," she said. "And the boys, when they get behind the wheel, they are the closest to their father that they could possibly feel. That's how they get to know and understand him."
This image released by Max shows Susie Wheldon, from left, Sebastian Wheldon, and Oliver Wheldon from the HBO documentary "The Lionheart." (Max via AP)
FILE - IndyCar driver Dan Wheldon, of England, signals his second win of the Indianapolis 500 auto race at the Indianapolis Motor Speedway on May 30, 2011, in Indianapolis. Wheldon is the subject of a new HBO documentary "The Lionheart," premiering March 12. (AP Photo/Michael Conroy, File)
This image released by Max shows Oliver Wheldon, son of Dan Wheldon, in a scene from the HBO documentary "The Lionheart." (Max via AP)
This image released by Max shows Dan Wheldon in a scene from the HBO documentary "The Lionheart," premiering March 12. (Michael Voorhees/Max via AP)
This image released by Max shows promotional art for the HBO documentary "The Lionheart," premiering March 12. (Max via AP)