Born and raised at Four Corners, their parents' thoroughbred horse farm in Kentucky, Charlotte and Knox grew up steeped in the rhythms of foaling season - the cyclical revolution of life and growth and change that transformed generations of foals into yearlings every January. Knox and Charlotte are as tightly connected - and as mysterious to each other - as two sisters ever were. When Charlotte leaves Four Corners Farm, and marries Bruce, a New Yorker, moving to Manhattan's West Village, their lives remain powerfully entwined. But nothing will solder their lives more deeply or fatefully than Charlotte's pregnancy, and the fateful day on which she delivers two glorious twin boys, and then dies in childbirth.

For Knox and Bruce, near strangers both devastated by the loss of Charlotte, the woman who connects them to each other more deeply in death than she ever did in life, the vast, inscrutable calculus of their grief is initially subsumed by the relentless waves of obligation and exhaustion which take hold almost at the instant of Charlotte's death: Together they take up the work of caring for her two motherless boys. In their mourning, and in the joy and desolation that flood in as their love for the children deepens, Bruce and Knox confront the deepest paradoxes of grief and regeneration, questions of loyalty and unalloyed longing, and the entanglement of families and generations. A gripping, powerfully affecting debut novel from a stunning new writer.