Can't remember the name!

I have a question, I've been trying for years to come up with the name of a book I read when I was very young. I'll try to give you the details I remember and PLEASE if anyone knows the name of it let me know!! Sorry the details will be totally disorganized and maybe not make sense but I hope they do!!

Ok so the protagonist is a young/adolescent girl, her family runs a farm, they definitely have farm hands living in the barn because I think she and her sisters find their dirty magazines at some point. I want to say it's set in the early 1900s but that could be wrong. They have a problem with gypsies who raid the farm every now and then. At some point her father gives her I think it's a white horse and I think it's for her birthday. She names him Prince (I THINK) but it's his secret name. All of her sisters get pregnant before they get married I'm pretty sure. I think she meets one of the gypsies and maybe she chases him on horseback half because he's stealing half because she thinks he's cute or something? She follows him and the gypsies across this river, it's all sort of mystical maybe, but their horses can swim it and it's too much for her horse so he drowns in the river.

THAT is all I can remember. I have a feeling the word queen was in the title but that could be totally wrong. If this sounds even REMOTELY familiar shoot me a message and let me know!! Haha it's been driving me crazy for a long time trying to think of the name of this book. It's probably buried somewhere at my house too is what kills me, but nevertheless, I'm beginning to ramble. THANKS! :D

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Wow. To be honest I have no idea.
I wish somebody helps you successfully
:(

If the horse's name is actually Prince, then maybe this would help.

http://en.wikipedia.org/wiki/List_of_fictional_horses