I'd only be concerned if in front of kids a little older than her may laugh if she says she has princess shoes on.
Though as a mom, (my baby is in college) you want to make something feel nice and like fun for our children when the reality may not be.
I guess it depends on if she is around the same kids(playmates) all the time, or familiar places often.
The princess shoe thing can go 2 ways, a positive approach or not so positive. Some kids are hurt when parents have told them a fib and then have to tell them the truth.
Will she have to wear them long? When I teacher aided for 2nd graders for 5 yrs., I saw a mix of behaviours,sadly to say a large percent were bullies,yes girls and boys.
Many parents are bringing their kids to be aggressive but there seems to be no boundaries where the aggression is appropriate. Personally I didn't care for a lot of the things I saw deteriorating over the years. Sorry, I strayed, but I feel it may not be necessary to fib, but maybe tell her the truth and that she will get better, and when the braces come off, you'll have a party for her.
It may even cool, if kids ask her about the braces, that she will have a real explanation, natutally teach her about that on a child her age level.
When we had children enter our 2nd grade class with some sort of handicap,ailment,allergies, and asthma, they would explain to the others what it was about and kids never made fun of them,but actually would alert us and others if the child had an attack or fall.
This is just my thoughts,for I really do not know you or your little girl,cyber conversations can be difficult,so I apologize if anything I said came out sounding unpleasant, I had no intentions of doing so.
I wish your little sweetie lots of luck with this,she'll do fine I'm sure. And I wish you,too,the same.
Sincerely,
DE

((((((((( Desirae and daughter )))))))))))


BTW
My husband,his sister, and nephew, had to wear braces too, for a little while,today they are all grown up and have straight,strong legs. My MIL,said my hubby's legs were also bowed and was pigeon toed, one would never know after things all settle in,the bones are still soft at that age so she shall do fine.