As a sequel of sorts to the Diane Sawyer 20/20 special, TV viewers will be able to follow Bruce Jenner's journey as he transitions into a woman in his forthcoming eight-episode docu-series on E! starting July 27. But it is allegedly his sons Burt, Brandon and Brody Jenner and stepdaughter Kim Kardashian who are hesitant to hear and watch just how much their 65-year-old patriarch will reveal about gender change. 'They are warning him to slow down on revealing too much of his journey on reality TV,' a source told TMZ in a Monday report. Scroll down for video . Follow-up: Bruce Jenner will chronicle his journey as he transitions into a woman in his forthcoming eight-episode docu-series on E!, a project that worries his kids according to TMZ on Monday . There is no denying that Bruce's six biological children and four stepkids are 'proud' of the father figure as some called him their 'hero' on Twitter shortly after the ABC interview aired on Friday. And as the former Olympic gold medalist moves forward with his long-awaited physical transformation, the spotlight and attention on him will be brighter than ever. 'Kim and the boys think Bruce was spectacular on the Diane Sawyer special and in won over millions of people in the process. His kids have gone to their dad to express their concern,' the insider told the gossip site. 'They say they're worried Bruce's upcoming docu-series might "de-class" what he's accomplished. They also urged Bruce not to do other interviews, and finish the process in private.' The only Kardashian: 'Kim and the boys think Bruce was spectacular on the Diane Sawyer special and in won over millions of people in the process,' added a source . Jenner sons: 'They are warning him to slow down on revealing too much of his journey on reality TV,' it was also shared . Brandon and his brothers: 'They urged Bruce not to do other interviews, and finish the process in private,' it was noted . Adding: 'Bruce believes the docu-series will educate people and create empathy, so he's committed.' On Monday, never-before-seen footage from the tell-all interview aired on Good Morning America that showed the Jenner brothers and Bruce's eldest daughter Casey talking about their childhoods in which Bruce was not around for. 'We have a very complex relationship,' Casey admitted. 'He's disappeared out of our lives, especially out of my life, so I'm looking forward to this next chapter.' Brandon spoke of Bruce during the years in the early '80s: 'Us missing a time of our lives is still the probably the hardest thing for us to deal with, we're trying not to look back, just looking forward.' Sticking together: Brandon and Brody share the same mother (second wife Linda Thompson) while eldest child Burt is from first marriage to Chrystie Jenner (pictured in May 2012) Older kids: Burt, Brody, daughter Casey and Brandon were the only children who appeared in the 20/20 interview . Struggle: '[Bruce] disappeared out of our lives, especially out of my life, so I'm looking forward to this next chapter' Bruce admitted he was not around for his children when they need him the most telling Diane: 'The big formative years for them I was really struggling with these issues. I talked to all the boys about this after the fact that, yeah, I didn't do a good job. And I apologized to my kids for that.' Those times appear to be a thing of the past as the Jenner siblings have now stated that 'all is forgiven.' While the Keeping Up With The Kardashians cast did not appear on the 20/20 interview - viewed by a staggering 16.9 million people - many speculate that ex-wife Kris Jenner and her children Kim, Kourtney, Khloe, Rob and Kylie and Kendall will be featured on the upcoming docu-series because it will be broadcasted on the E! network. However, TMZ's sources cited that 'Bruce's kids won't appear on his show.' Love no matter what: During the interview, Bruce stated that Kim was 'by far the most accepting' of his transgender journey . Growing up without their father: 'Us missing a time of our lives is still the probably the hardest thing for us to deal with, we're trying not to look back, just looking forward' With the hope that his reality show will be both informational and educational, Bruce has signed a contract with E! to air one hour episodes starting July 27 that will be consulted by the Gay & Lesbian Alliance Against Defamation (GLAAD) organization. Jeff Olde, Executive Vice President of Programming and Development at E!, said of Bruce's decision to share his journey with the world: 'Bruce is incredibly courageous and an inspiration, and we are proud to be entrusted with this deeply personal and important story. 'This series will present an unfiltered look as Bruce boldly steps into uncharted territory and is true to himself for the first time.' Bruce's representative told MailOnline: 'Can't put a series on hold that has yet to be confirmed as even happening in the first place.' Champion: 'Bruce believes the docu-series will educate people and create empathy, so he's committed' His pride and joy: The former Olympic athlete told Diane that his kids are 'the only one's he's concerned with' On Sunday, eldest child Burt doubted some of his dad's newfound supporters when he took to Twitter writing: 'Having a hard time not putting a few people on blast who were not supporters before hand, but want to act like they were all along.' Meanwhile that same day Brandon and Brody - whom Bruce fathered with second wife Linda Thompson - shared photos of themselves with their famous parent. 'You won another gold tonight. I stand with you on this journey. I love you Dad,' the former Hills star commented on Saturday. 'Proud son,' the father-to-be - who was the first to be told by Bruce about the transition - wrote before the ABC interview aired on Friday. Kim spoke to Today Show's Matt Lauer on Monday revealing that Bruce has 'found inner peace' after speaking his truth. The other side of Bruce's family: Biological daughters Kendall and Kylie and stepdaughters Kourtney and Khloe were pictured on Thursday with mother Kris Jenner . Spotlight: E!'s Keeping Up With The Kardashians has been featured as a hit reality show for ten seasons now . During the 20/20 special, the thrice married star and host Diane shared that it would be the last interview would doing as Bruce and that he is ready to embrace the woman he calls 'Her.' The star expressed that he 'is a girl stuck in a guy's body' and that 'his brain is much more female than it is male. 'Yes I am a woman, my heart and my soul and everything I do in life,' he said. 'That female side is who I am.' When asked by Diane to fill in the blank 'When you think of me...' Bruce gave a heartfelt response saying: 'Please be open minded, have an open mind and open heart. I'm not this bad person I'm just doing what I've got to do.' 'If he's happy, we're happy': Kendall and Kylie were the only offspring to give an official statement for the ABC special .
Bruce is set to star in an eight-episode docu-series on E! starting July 27 .
Kim, Burt, Brandon and Brody 'don't want him to do the series'
Jenner's sons and daughter Casey tell GMA the star left them in the '80s .