I slept-watched through the last two movies. Was there any logical (in the world of the movie, that is) explanation behind the granddaughter thing, or just a forced shift that had nothing to do with previous plotlines?

And in the prequels you find out Annakin is Space Jesus/Herakles. Btw younger people seriously need to stop pretending the prequels aren’t dogshit.

she’s dead Palpatine’s granddaughter

Wasn’t Luke also Palpatine’s grandson because he caused Anakin’s mother’s pregnancy?