I knelt down in front of Emma, my heart pounding, and tried to keep my voice gentle even as my mind raced. “Sweetheart, nobody is in trouble. I just need to understand. Who is the little girl?” Emma looked at Ryan, then back at me, her small chest heaving. Ryan crouched beside her and nodded softly, giving her permission she seemed desperate to have. “Her name is Lily,” Emma whispered. “She’s my sister.”

The word landed like a stone in still water. I looked up at Ryan, bracing for the worst, for the confirmation of an affair, a secret second family, everything the babysitter’s careful silence had implied. But Ryan’s face wasn’t guilt. It was grief. “Diana,” he said quietly, “she’s not what you think. Lily isn’t the result of anything that happened during our marriage. Please, sit down. I should have told you this years ago, and I was a coward not to. Emma found out by accident four months ago, and I’ve been protecting a secret that was never mine to keep from you.” He took a breath. “Before you and I ever met, I donated to a fertility clinic. Lily is the child. And six months ago, her mother reached out to me, because Lily is very sick.”