I sat there, staring at the woman who had raised me, feeling like my entire existence had been erased and rewritten in a single second. “I’m adopted?” I whispered.

She nodded, her shoulders shaking. “We got a lawyer. We sealed the records.

We made a new birth certificate. We did everything we could to protect you. I thought if you knew, you wouldn’t love us the same way. I was so scared of losing you, Clara.”

I didn’t feel angry at her. I just felt numb. But then, my brain, still trying to process the medical nightmare from earlier, started putting the pieces together.

“Wait,” I said, leaning forward. “If Sarah was my mother… what was her blood type?”

My mother wiped her eyes with a crumpled tissue. “I don’t know, honey. I don’t remember. But your biological father… he was a man Sarah met in college. He was a B positive. I remember that because Sarah had a rare antibody issue during her pregnancy.”

My mind was working fast now. If my biological father was type B, and my biological mother was whatever she was, then I wasn’t genetically type A. Or maybe I was, but my genetics were different than what I had believed. I looked down at my own medical records. I had always been typed as A positive.

But wait. Even if I was type A, and my adoptive parents’ blood types didn’t matter because I was adopted, it still didn’t solve the main problem. The baby inside me was AB positive. He had an A allele and a B allele.

I was the mother. I carrying this baby. So I passed on either A or B. Since my blood type was A, I passed on the A allele.

That meant the baby’s father *must* have passed on the B allele.

But Mark was type O. Mark only had O alleles. He couldn’t pass on a B allele. It was still biologically impossible for Mark to be the father, even if I was adopted.

I felt a cold wave of despair wash over me. The adoption secret explained why my blood type didn’t match my parents, but it did absolutely nothing to save my marriage. To the rest of the world, and to Mark, I was still a cheating wife.

I drove back to Fort Wayne in complete silence. The rain had stopped, but the sky was a dark, bruised purple. When I walked through our front door, Mark was standing in the kitchen. He had made dinner, but the plates were untouched on the counter. He looked at my face, and he knew.

“Clara,” he said, his voice cracking. “What did the doctor say?”

I walked over to the kitchen table and laid out both birth certificates. The fake one from my baby book, and the real one from the yellow envelope. I told him everything. I told him about Sarah, about my adoption, about my biological parents. He listened in silence, his eyes wide, his hands gripped tightly around his coffee mug.