"Mary K. is your daughter," I said, hating hearing my voice crack. "Biologically. But I'm nobody!"

"Don't say that!" Mom said, looking devastated.

"You're both our daughters," said my dad. "And you always will be."

It was about the most comforting thing he could have said, and it made me burst into tears. I was so exhausted, physically and emotionally, that I stumbled upstairs to my room, lay on my bed, and began to drift toward sleep.

While I was half dreaming, half awake, my mom came into my room and sat on the bed next to me. She stroked my hair, her fingers gently working through the tangles. It reminded me of my dream, my other mother. Maybe it wasn't a dream, I thought. Maybe it was a memory.

"Mom," I said.

"Shhh, sweetie, sleep," she whispered. "l just wanted to say I love you, and I'm your mother, and you've been my daughter since the first second I laid eyes on you."

I shook my head, wanting to protest that it wasn't true, but I was already too close to sleep. As I drifted off into a deep, blessed numbness I was aware of warm tears soaking my pillow. I don't know if they were hers or mine.

The next morning was bizarre in how ordinary it seemed. As usual, Mom and Dad got up and went to work early, before I was even awake. As usual, Mary K. yelled for me to hurry as I drifted through my shower, trying to brace myself for the day.

Mary K. looked pale and pinch faced and was unusually quite as I gulped down a Diet Coke and threw books into my backpack.

"I want you to stop what you're doing," she said so softly, I could barely hear her. "I want us to go back to being how we were."

I sighed. I had never felt jealous or competitive when it came to Mary K. I'd always wanted to take care of her. I wondered if it would be different now. I had no idea. But I knew that I still hated seeing her hurt.