Let’s Build a Miracle is a high-stakes, heart-forward story about a father, his twin daughters, and a forgotten rover on Mars. When a single dad and his girls decide to wake Opportunity and guide her across the planet to reunite with Spirit, they spark a moonshot nobody asked for—and everyone starts to need. Their edge is HOPE, a scrappy helicopter built on a shoestring—and the belief that whiteboard-to-wrench breakthroughs can add up to the impossible. Budgets, politics, and Martian winter all press against the clock. “Small but mighty”—that’s the rover’s motto. It becomes the family’s, too. After reading about the twin Mars rovers, Miranda and Eloise fix on a child’s clear injustice—that the sisters never ended together. Their father, a space-obsessed Hill staffer drowning in his own divorce and midlife drift, turns their wish into a plan: a grassroots, NASA-realistic attempt to wake Opportunity and guide her across Mars. A ragtag “B-Team” rallies behind him: a scarred rover engineer, a gifted but unproven coder, a comms rockstar, and pragmatic systems leads who know what failure costs. With no fanfare and almost no funding, they build HOPE —a lightweight helicopter that can scout ahead, carry heat, and act as a pathfinder. The project’s constraints are brutally real: dust storms, failing batteries, light budgets, orbital delays. Success means learning to balance devotion and delusion. For the father, the home front becomes its own control room. The twins chart routes across the dining-room table, fall asleep under star maps, and grow up in sync with a machine slowly relearning how to move. Mars becomes a mirror for their coming-of-age: each small advance a lesson in persistence, each silence a lesson in grief. When Opportunity finally answers—a flicker of telemetry, then movement—the victory is quiet but holy. Progress unfolds in whiteboard fixes and whispered celebrations. Over years, as the rover inches across the planet, the girls grow from eight to eighteen. What began as make-believe becomes a shared vocation that binds a family, a team, and a dream. But Mars tightens its grip. Communication gaps stretch into weeks; the helicopter stalls; the rover faces terrain that punishes optimism. On Earth, political pressure mounts: a grandstanding senator threatens to seize control of the mission. The team answers with the only currency they have—progress—and redesigns around sacrifice. They cut safety margins, push past “no-go” zones, and trust the machine to make her own decisions. At its core, Let's Build a Miracle isn’t about hardware but about inheritance—the passage of curiosity, courage, and care from parent to child. The mission’s decade-long traverse across 10,000 kilometers of Martian desert becomes an allegory for endurance: of families, of faith in work, of belief that something small can still matter. By the final pages, Opportunity’s voice fades again, but she is not alone. The daughters, now young women, have taken up the controls of their own lives, carrying forward the same stubborn optimism that once animated their father’s impossible project. Written in lyrical, precise prose and grounded in real NASA engineering, Let's Build a Miracle bridges literary and speculative fiction—a meditation on science, devotion, and what we choose to carry to the finish.