Well, there's one girl who commented back saying her essence is Princess Vasilisa which does fit our criteria to help you. However, Roxas replied and he's The Little Mermaid. We recently fixed that book and with the edits, the Mermaid does marry into royalty so it's a question on whether that counts. Finally, there's someone who is the Snow Queen inquiring if being a Queen counts at the implication they may have been a Princess prior which is something else to think about.

[Not that it probably does since the Snow Queen... hm, she didn't really have a backstory so it could be possible...]