When Kirk Franklin began working on a new album earlier this year, the Grammy-winning musician had no idea what was in store.

"This is the first time I've had a behind-the-scenes videographer capturing content for the making of a project," Franklin, 53, says of working on his 13th album. "I recorded the first song in March. Then in April, everything shifted and became something I could have never planned for."

What the cameras ended up capturing was an intense, emotional journey the star went on after suddenly learning who his real biological father was. He also saw it as an opportunity to reconnect with his estranged eldest son Kerrion, 35, whom he hadn't seen in a decade.

Franklin has compiled the footage from these events into a short documentary streaming on September 15 on his YouTube channel ahead of the October 6 release of his new album. Both projects are aptly titled Father's Day.

Now Franklin is sharing with PEOPLE what all it's taken to get to this point, along with an exclusive clip of the moment his doctor delivered the news of his biological father's paternity.

"My life before I had a career was horrific," says Franklin. Long before he became the guiding voice of gospel music, orchestrating decades of hits like "Revolution" and "Wanna Be Happy?", Franklin experienced a tough childhood growing up in Fort Worth, Texas, where he was adopted at age 4 by a woman at his church.

According to Franklin, his birth mother, then a young teen, was unable to care for him. Though he knew who she was, they rarely connected during his youth and he often felt abandoned.

"I lived being bullied as a kid. I had a learning disorder, I failed out of high school. I got a young lady pregnant when I was 17 and the church crucified me for it," he says, recalling his early hardships. "It's like I never had anybody take up for me or who had my back."

As for the woman who adopted him, "She was 64. She was a widow and did the best she could when I was young. She got on government aid and would find money to pay for my piano lessons," he says. "But by 12 or 13 I felt abandoned by her because I could tell I became more of an irritant. I wanted to date and go out and I always felt like I was inconveniencing her. It just added to the feeling of displacement."

When Franklin was 6 he was introduced to a man his biological mother said was his biological father. "I didn't see him again until I was 13 and then he started showing up at concerts after my first album came out," he says. "I was angry at the fact that I did not have a father and he would dare show up once my life seemed to have some sense of order. Same for my biological mother." Franklin says she, too, began to turn up more as his career took off. "It was very traumatic for me."

The man Franklin long thought was his biological father died in recent years. But while recording his new album, a singer he had hired from his hometown told him that she'd met a man at a funeral who said he'd once dated Franklin's mom.

The man's name: Richard Hubbard — and he's lived in the same neighborhood Franklin grew up in all of his life.

As rumours swirled that he might in fact be the star's father, Hubbard submitted a DNA test. The results were a 99.9 per cent match for paternity. "To live over half a century with somebody who lived in the same city as you..." says Franklin, who is still grappling with the news, "I suffered so much as a young man without guidance. I struggled with love, intimacy, faith, identity. And to know that the answer was less than 10 minutes away."

The documentary captures an emotional first meeting between the star and Hubbard, who was 14 or 15 when Franklin was born and says he never knew he'd fathered a child at that time. "He is a great guy," Franklin says Hubbard, who also has a daughter. "She's been honest about how hard this is for her as well, learning not only does she have a brother but that that brother is Kirk Franklin."

Despite finally knowing the truth, Franklin says things aren't perfect. As shown in the documentary, his biological mother refuses to accept the DNA results, even after a second test was completed.

"She's just very adamant that this man is not my father," he says. "I have not heard or talked to her since the second test result."

Someone he has reconnected with is his own son, Kerrion. The two have had tension for years and experienced a very public falling out when Kerrion released audio of a heated conversation with his dad in 2021. Prior to the meeting shown in the documentary, it'd been two years since they'd spoken.

"My son is a beautiful soul. There are parts of his life that are his to share. I am just very proud that I'm seeing him in his own way," says Franklin, stopping short of detailing what all plagues their relationship. "He is beginning to reveal and testify to his struggles, his own battles with certain things that have at times cost him. I know many young Black men struggle with these same things and as he continues to get help and healing he's going to help so many. He has me and now his grandfather that will be there to help in any way we can."

After all that's transpired this year, Franklin, who's also father to daughters Carrington, Kennedy and son Caziah with his wife Tammy, has been reflecting on his own experience as a dad.

"I have fathered out of fear the majority of my parenting life," he says. "Because of what I experienced, I was like 'I'll be damned if I let my kids feel that type of pain.' So a lot of times I over-parented and over-performed, bought too many bicycles, ran off too many boyfriends, just wanting to protect."

"I had to learn," he adds. "My children have been the best part of my life."

He's folded all of these experiences into his inspirational new gospel album. "The title Father's Day has triple meaning," he explains. "The logline is, 'It's what I missed, where I am and what has always been.'" And after all he's been through, "even when I want to curse the sky," he says, "I'm still built to believe."

Franklin's new documentary Father's Day is streaming on YouTube.