As it turns out, Sarah, as a child, had also sprouted wings, only to have them first painfully bound, then brutally amputated by her own mother. Sarah had run away from home a few years later and had never come to terms with her distress about her lost wings. Linnet later discovers that her grandmother, Sarah's mother, had also grown wings on the brink of adolescence. Linnet's life begins to unravel quickly after these unsettling discoveries. Here, Linnet befriends a cynical teenage girl named Andy, who is tired of living in hiding and wants to take her chances living openly in the world.
Linnet also discovers that there is a large, but secret, worldwide network of winged people.
Linnet begins to agree with Andy that a lifetime of hiding is unacceptable, even if living in the world means being seen as different. Andy and Charlie, a young man with mutilated wings, both were unwanted by their families. However, as Linnet discovers, hiding prevents them from recognizing, helping, and supporting one another. Much is made of flying in Growing Wings. None of the characters can do it or even knows whether it is possible.