Good question (and you’re damn right about Kitty and Rachel)!

Jean Grey’s relationship with “her” kids is incredibly weird, even by comic book standards.
Because she comes from the future of Earth-811, Rachel’s relationship with her parents has been affected quite profoundly by the fact that she comes from an alternate future and thus hasn’t yet and might not be born in Earth-611. This was more of an issue with Scott to begin with, since Jean was dead and Scott had married Madelyn and had Nathan (who didn’t exist in Earth-811), giving Rachel something of an identity crisis, and making her relationship with Scott rather awkward.

When Jean finally met Rachel, Jean was dealing with having memories of her Phoenix self and Madelyn in her head, and thus was not quite ready to be a mother to a young woman she hadn’t given birth to (yet), especially given Rachel’s connection to the Phoenix Force through her mother, which brought up issues that the reborn Jean wasn’t ready to deal with either. So it took a while for them to gel.
Nathan Christopher Askani Dayspring Summers Cable is even weirder. He was born to Scott and Maddy originally, but then Jean subsumed Maddy’s memories, so Jean is in this weird
Schrödingerian situation where she both did and didn’t give birth to him at the same time that she remembers Scott abandoning the kid and other-her to be with her. But in the course of the original run on X-Factor, Jean dealt with her issues for Cable’s sake…only to have to give up the child in order to save him from the technovirus. And then the baby came back to her as a man who was older than she was, which is pretty damn awkward even if he hadn’t been a hard-bitten soldier from the future.
So overall, the thing about Jean Grey is that she’s never been allowed to get pregnant, have a kid, and then raise that kid. Which I think is a damn shame. There are a ton of examples of how to make interesting stories about superhero moms and kids: Hopeless’ run on Spider-Woman and Slott’s “Renew Your Vows” (to say nothing of the FF, Power Pack, Luke Cage and Jessica Jones, etc. etc.)
