⚠⚠⚠!!!!SPOILERS FOR SEASON 15!!!!⚠⚠⚠
Like I'm sure the rest of you are, I was devasted by the ending of season 15 and Nya's death, and Kai didn't even cry. I don't think the situation really hit him. For Jay, he just lost a lover, and while his emotions should not be overlooked Kai has a much deeper bond with her than anyone. He raised her after their parents were kidnapped. He always made sure she was safe. When he couldn't he still did all he could to make sure she was prepared, he let her do her own thing even if he didn't like it, he always had to be that stronger big brother.
The situation didn't hit him and he's still in denial.
I'm hoping next season is Kai focused and how he's dealing with the loss of his little sister. We might even get that evil Kai storyline in the future as Kai deals with his grief. But we all must be prepared because let's face it, Ninjago is going to be very different from now on with the passing of Kirby Morrow and now the death of Nya. I am not gonna sugarcoat this, it might be rough to some Ninjago fans but thankfully this community is tough and we'll help each other through it.