St. Paul, Minnesota, 1946: As little girls, the Malone sisters relied on each other for companionship and affection as their mother remained distant, beating back the demons of her own mysterious childhood. Now, as young women ready to embrace promising futures, Eliza plans for a life of intellectual fulfillment beginning with college at nearby St. Catherine's, while far simpler hopes for family and happiness occupy Shannon. Instead, the closely-knit sisters endure two life-changing tragedies and their powerful bonds of love and loyalty threaten to break under the weight of trauma and loss, secrets and misunderstandings. One sister leaves, possibly forever. Heartbroken and scarred from a battle with tuberculosis, the other vows to never let go of the invisible thread that runs between them--and in the course of her journey, discovers the true meaning of family.