The feud between the Kardashians and the Jenners got really ugly this past year, but did you know the feud is actually decades long? Yes, it goes all the way back to when Kris and Bruce, now Caitlyn, were first married.

Burt, Cassandra, Brandon, and Brody Jenner are Caitlyn’s kids from her first two marriages. By now, everyone is aware that Caitlyn, then Bruce, was MIA from her children's lives for years after she married Kris. Once the couple had Kendall and Kylie, it strained the already fragile relationship Caitlyn had with her kids, so she basically stopped showing up.

The tension mounted even further when the hit E! show aired, thrusting the entire Kardashian clan into the spotlight. Not only were Kourtney, Kim, Khloè, Rob, Kendall, and Kylie’s lives front and center for the world to see, Caitlyn’s relationship with her older kids started to come to light. Especially since Brody and Brandon had already been the subject of the FOX show Princes of Malibu. It also played out in a storyline on The Hills, which Brody eventually became a regular cast member of.

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While their siblings are all about the spotlight, both Casey and Burt are much more private. They have not appeared on the show at all. In fact, one of the only public interviews they took part in was when Bruce revealed he was transgender in the Diane Sawyer interview. Both were on hand to show their support for their dad. They have never talked about their personal relations with their father or their famous reality TV step-siblings.

In 2013, Brody confronted both his dad and his stepmom at different times. In one episode, he attempted to talk to Caitlyn (then Bruce) about not being around when Brody and Brandon were kids. However, he got brushed off by his dad claiming that was not the right time to talk about it. Then on a family vacation to Greece, Brody flat out told Kris he believes she is the reason he and Brandon have no relationship with their father. It was sad, ugly, and not a whole lot was resolved. His relationship with the family became more strained when Kim refused to invite his longtime girlfriend to her wedding.

Animosity between the Jenners and Kardashians hit an all-time high when Caitlyn did her tell all interview with Dian Sawyer. It was the first time she admitted she was transgender. Burt, Casey, Brandon, and Brody were on hand to support their father. However, Kourtney, Kim, Khloe, Rob, Kendall, and Kylie—the children she raised—did not participate in the interview. Even Kris refused to give a statement to ABC News, but his first two wives did.

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After Kris and Caitlyn split, and Jenner began her transition, the entire family dynamic changed. Jenner began trying to mend her broken relationship with Brandon and Brody, while the Kardashians all began to distance themselves from her. They did show up to support her when she accepted the Arthur Ash Courage Award at the ESPY’s, but Kris’ hurt feelings about her children supporting Caitlyn made it clear that lines were soon going to be drawn. She referred to them as being disloyal to their mother.

Caitlyn and Kris did share an emotional confrontation on I Am Cait, where they decided to put their kids first and mend their relationship. However, their truce was short lived as Caitlyn was writing a memoir that would divide the family forever. When Kris got an advanced copy from her ex, she was floored to learn what she had written about her. It is the perfect case of she said she said. Cait insists she gives a true depiction of her life with Kris, while the momager insists she was purposely painted as the scapegoat villain.

The biggest issue the Kardashian family had with the memoir was Catilyn insisted Kris knew she was transgender early on in the marriage. Kim, Khloe, Kourteny, and  Rob eventually cut ties with their former stepfather over the “lies” in the book. Both Kim and Khloè have been very vocal about the lies and publicly support their mother. Although at one point, Kendall did get angry with her father over the book on camera, she can be seen with Caitlyn every now and then on social media. Neither Kendall nor Kylie has spoken publicly about the rift between their parents.

Most recently, Caitlyn shared she does not talk to any of the Kardashian children. She maintains to be closer with her Jenner kids, but she also chose to skip son Brody’s wedding this past weekend in order to work. However, she can often be found on Brandon or Burt’s social media accounts.

Speaking of Brody, he claims he has not seen either one of this little sisters in a very long time. He has said he did not know Kylie was pregnant until it was revealed on social media. Plus, before he wedding, he made it clear he did not get an RSVP from Kendall or Kylie, who were both invited to his Bali wedding.

There is definitely no love lost between the Jenner’s and Kardashian’s. Sadly, it seems even the younger Jenner girls have chosen a side. This is one family feud that appears to be never ending!

NEXT: CAITLYN JENNER OPENS UP ABOUT RIFT WITH KIM KARDASHIAN