In her breathtaking new memoir, Phenomenal: A Hesitant Adventurer’s Search for Wonder in the Natural World published Tuesday, Leigh Ann Henion, 37, writes of the birth of her 5-year-old son Archer: “I love and marvel over him as if he were my own heart pushed into the world and, still beating, set on top of my chest. Yet I cannot help but mourn the loss of something I can’t quite place. I have an inner emptiness—literal and figurative—that I’ve never felt before.” What follows is a raw, sometimes gut-wrenching account of the dark and lonely place Henion finds herself in...