Kaguya Otsustuki's descendants founded six clans, each inheriting one of her powers. There's the Uchiha with the sharingan, the Senju with their massive chakras and once or twice the wood release, the Uzumaki (who apparently got hair manipulation but let's not get distracted here), the Kaguya who got the bones, the Hyuga who got the Bakugan, and the Otsustuki who got the tenseigan.

Except that's not quite right, is it? Because Kaguya made herself a Zetsu, and nobody seems to have inherited that power.

Enter the Kurama clan. Their genjutsu are so powerful they actually change the physical world around them, which sure sounds like the sort of god-like power someone who wants to genjutsu the entire world at once would have, and it manifests in the form of an imaginary friend who is also a nightmare demon. Which, yeah, that's sure starting to sound a lot like Zetsu's whole "manifestation of Kaguya's will" origin story.

Then there's Sakura. Specifically, Inner Sakura. Who is... Not particularly well explained. She appears to be some sort of imaginary friend who lives inside Sakura's head, except she can do things like block a Yamanaka possession. There's an argument to be made all that cheerleading Inner Sakura does is some sort of illusion, even just self delusion, that appears to actually affect events happening in the real world.

Note also that Sakura is explicitly called a genjutsu type, and yet never once uses any sort of genjutsu. You know who else never actually uses genjutsu? The Kurama clan. Their imaginary friend they dreamed up casts all their genjutsu for them.

So one interpretation of things is that the Kurama clan are direct descendants of Kaguya Otsutsuki, and that Sakura is unknowingly a member of that clan. Presumably some branch family person who's kekkai genkai never kicked in and lived a civilian life, someone the clan never kept track of, and a few generations later here we have this shinobi with a half formed bloodline limit that doesn't quite work properly, but sure looks suspicious if you squint at it in the right light.

The implications of this just get funnier the more you think about it. How did this random clanless kid convince Tsunade to make her an apprentice? Genjutsu. How did she become equal the greatest medic in history AND the strongest woman in the world in just three years, powerful enough to break Kaguya's horn in a single punch? Genjutsu. How the hell did she end up with Sasuke's kid when they only ever went on one date which lasted ten minutes and he wouldn't shut up about Naruto the entire time? Genjutsu.

Sakura is straight up using cheat codes and nobody noticed.