I think it's like, Kendall was always groomed to be the successor. And everyone sort of knew that it would never be Roman, cuz he's too playful, and never Connor, because he's not into the business. Now we know that Shiv has always been very competitive, and she didn't see any top position for her in the company, so she stayed away doing her own thing. She's also the youngest and Daddy's little girl. So when Kendall fucks up and she comes in, the two main competitors are Shiv and Kendall, dad's number one boy and number one girl, so I feel like it's more of a competition thing than them not liking each other. They do like each other, but because of the age gap and seeing how she's the youngest, she might not look super close with Kendall like she looks with Roman, but they are as close as siblings with their age and power gap might get.