Seeing how the princess mother act and how she saved the servant... I suspect they were ch...

Agreed kinda, I don't think they were switched. Their both princesses. I think the maid (I can't remember these gosh darn names D': ) Was just given to the nanny for protection. Maybe save one daughter and sacrifice the other. Maybe that was her mind set. Which is why she had no feeling sending her away. She didn't want to get attached hence will lead to her getting her heart broken? Honestly from what I saw in the flash back, she was tied up and gagged possible during the child birth? O_o or maybe it was just something for her to bite and hold onto? I don't know but I like my theory xD