I Might Come Back To This - Tumblr Posts

this scene in return to del hit so hard
I find some parallels for Kairi and Namine interesting, the ones that’s either intentional or something that happened retroactively.
Sharing an ability for art. KH1 Kairi drew on cave walls and crafted a charm out of shells, but then you got Namine's drawings which is more front and center as the focal point of her powers.
Star shaped charms. One is made out of thalassa shells and the other is modeled after a paopu.
Both have been trapped and used by the organization for their own ends at some point, usually to pretty devastating effects.
As of MoM, they both have some level of memory powers. Namine manipulates those of the people connected to Sora ( and likely Kairi ), while Kairi is able to dive into her own memories and seemingly of those connected to herself. Also let's be honest they could both probably expand on said powers.
There's probably more but these are the ones I can think right off the top of my head.