What is meant to be is bound to happen, whether or not you approve.”
-- Narrator (Part One: Intuition)

Importance: This quote is about fate. Throughout the novel, fate plays an important role, emphasized by the family curse. The fate of the Owens family is to at first fight fate in fear of the inevitable consequences, but to ultimately learn to accept that whatever is meant to happen will.

Her wish was entirely whole and absolutely perfect. She knew how to ask and had been very specific . . .”
-- Narrator (Part Two: Alchemy)

Importance: Knowing how to wish for things is a metaphor for setting goals. To get achieve a goal a person must know specifically what they want, or the chances of following through to the finish are greatly diminished. By emphasizing that the only way have a wish fulfilled is to be specific shows that the author thinks of wishes like goals.

She never thought to choose courage,’ Isabelle said.‘But...
-- Isabelle Owens and Franny Owens (Part Two: Alchemy)