Here is another one of my theories. BTW sorry about my last post it was a misunderstanding.  Any way I just figured out something else about the princesses. Princess Celestia is a very wise adult. Even Nicole Oliver said in a convention that she seems more like a queen. So why not? If Princess Celestia and Princess Luna are princesses, obviousley, that means their parents are still alive. So where are they? Let me explain. For example princess Anna and queen Elsa 's parents died in the begining of Frozen. Which made Elsa queen because she is the oldest and Anna is next in line. Just like Celestia and Luna. If there parents died Celestia should be Queen and Luna is next in line, Right?

One more theory this time it's about Cadence. Speaking of Kings and queens, there is another mystery I'm trying to solve. If cadence is already married she is considered queen, right ? I don't know. Could be another mis understanding about her. One more thing. if shining arnor got married to a princess. that means Twilight was already royalty from season 3! Has anyone else thought about that? She could have been princess already if Celestia didn't give her a task to do.Although Princess Celestia's way was totally better.  If I'm wrong about anything I posted in here please comment. I would love to hear from you. AND if you have questions That need answered then post a commment about it and I'll answer it  by making a blog post. : )  Your questions could be about any character or theory. i'll try my very  best to solve and answer it.