Point of View?

Dear Jennifer Weiner,

I recently read your book Little Earthquakes, and I have a question.  Why do you tell three of the characters' stories in the third-person but tell Lia's story in the first person?

I'm really curious about your choice from a writing standpoint.  Is it because Lia lost her baby, and the others didn't?  Did you want to share her kind of loss from a first-person perspective?  Or is Lia supposed to be the narrator of the story?  If so, how can she possibly know the others' stories?  Or is she just the narrator of her section?

While I really enjoyed the book, I was continually jarred whenever I got to one of Lia's sections.  I'd be lost in the story, and then all of a sudden, I'd have to remember who the "I" was.  I kept thinking there was a reason why you wrote the story this way--and as a writer, I'm curious to know that--but as a reader, it hurt the flow for me a little bit.

If you get a chance to let me know, I'd appreciate it.  In the meantime, I'll be reading more of your stuff--I'm learning a lot about good storytelling from you.

Thanks,
Your pal,
Jill