I was pondering that question cause when i was on the website four 358/2 days and it showed Xion and Roxas next to each other they looked alot alike so i wondered if she might have been soras sister and he didnt know about her cause she died and they were seperated or sumthing. idk tho so give me wat u think.
heres the website
KINGDOM HEARTS 358/2 Days | SQUARE ENIX
heres the website
KINGDOM HEARTS 358/2 Days | SQUARE ENIX