I think a lot of the speculation re: Kaylee being the target was wildly exacerbated by how vocal her dad was in the media before they arrested someone. I will never tell someone how to grieve and I'm not even going to pretend to remotely understand how they are feeling but I thought from the beginning her dad was putting a lot of emphasis on her as THE victim - detailing her injuries, saying only she had defensive wounds, saying "he didn't have to go upstairs" (what does this even mean and why would he think that?), even suggesting Kaylee could have ripped the sheath off of her attacker before sadly succumbing to her injuries? You can't rip leather like that especially while fighting for your life and if that was the case the PCA probably wouldn't have specified the sheath only contained 1 source of DNA, later believe to be Bryan's.
I wouldn't expect them to put the same focus into someone else's kid(s), but for me personally, I've tried to avoid any media with him in it because all four victims and their possible links to their killer need to be explored equally. His adamancy about her having a stalker/knowing the perp, and then once BK was arrested he immediately said there was no connection between them, goes to show at least some people were right in saying he was doing too much to keep focus on the case. I also don't agree with any family saying right off the bat, "my kid didn't know this person whatsoever" unless that has been confirmed after forensics on the electronics, you absolutely do not know every single person your kid has interacted with.