Ann Patchett's 'Commonwealth' brilliantly unravels the complex tapestry of two families irrevocably intertwined by a single, fateful decision. When Bert Cousins crashes Franny Keating's daughter's christening party, an unexpected affair ignites, leading to the dissolution of two marriages and the blending of six children into a new, often volatile, household. Spanning five decades, Patchett expertly explores themes of loyalty, betrayal, love, and the lasting repercussions of secrets. The novel delves into the intricate dynamics of a modern family, showing how a childhood pact, a shared secret, and the eventual publication of a fictionalized account of their lives shape their identities and relationships, leaving readers to ponder the nature of truth and storytelling.