327Q: Glass/Crystal Palace

I read this book in the late 1990s. It’s a picture book, with detailed illustrations. I remember rich colors, and I think they looked like watercolor paintings. What I remember of the plot: there are two princesses (maybe they’re cousins), and one lives in a castle or palace of crystal or glass. The other princess comes to visit her in her glass/crystal palace, and she arrives by boat—I think the illustrations are of a city similar to Venice, where the streets are canals, and I remember fun bridges with lots of stairs. I was intrigued by the details of the buildings in the drawings. Part of the story may have been that the princess who comes to visit lives in a palace made of some other specific material—brick, stone, wood—something like that, but I’m not certain. And she decides that she would rather go back to her palace of glass.

327I: The Missing Blond Princesses

I’ve been looking for a book that I started reading sometime during third grade (which would have been around 1998 or 1999), but wasn’t able to finish before my teacher gave away various books to another teacher.
Obviously, I have no idea what it was called, but I remember it was not a picture book. I don’t remember what the cover looked like, but I imagine that the title said something with “Princess” in it, and something that would have sparked the interest of a 3rd grader. I also don’t recall the author or the year the book was published, but it would have been before 1999. I also don’t remember any names of characters or places.
What I remember from the book (if I’m remembering correctly) is that the protagonist is an ordinary blonde girl, who lives in modern times and is somehow whisked away from her life to a fairy-tale-like world and told that she is going to be the next princess of whatever world she is taken to. What she learns is that every princess before her was also blonde, but mysteriously went missing. This world she is taken to has strange birds that fly in the sky (based on what I pictured/remember thinking of when I read the book – again there were no pictures – but I imagined they were vulture-like). People are afraid of these birds, as they also believe these birds have taken the missing princesses. What the protagonist seems to start to uncover, however, is that these birds might actually be the missing princesses – maybe some kind of curse or something.
That’s either how far I got, or all that I remember. I know it’s not much to go on, but it’s been bugging me for years.