Mercedes is the one who demanded I meet her at Laurel Park and tell her everything I know, but now she’s the silent one. A scrawny squirrel runs near us and then darts away, climbing the huge tree next to the swing set. Lucas showed me and my mom this park while Bob was busy with the movers. It’s the closest playground to the house, but it’s so small compared to the parks in the Saint Paul neighborhood I played in when I was his age. This one is just a slide and two swings. Mercedes and I swing back and forth on them now, neither of us speaking. I think of Mai, who never stops talking.

I told Mercedes that I haven’t said anything to anyone about us, but that’s not quite true. I called Mai and told her about my doppelgänger—or sister. Half sister. Whatever she is. Telling Mai made it a little more real to me, but I wish I could have told her the secret in person. FaceTiming isn’t the same as seeing each other at school.

“A sister? A secret sister?” Mai said. Her eyes got huge and then crinkled in an excited giggle. “Okay, what if she knows your dad and then you get to meet him and then your parents get back together like in that one movie—”

I cut her off. “My mom just married Bob,” I cried. “Even if I ever met my dad, I’m sure they wouldn’t get back together. I wouldn’t want them to. My mom’s happy now.”

“But a sister!” Mai gushed again. “I know I complain about Houa and Eve, but I love having sisters.”

Mai has a huge family—two sisters and four brothers—and lives with not only her parents but her grandma and aunt, too. Because she has such a big family, Mai takes care of her little brothers and sisters since she’s the oldest girl. She also helps cook every night. Once a month her parents let her sleep over at my house.

“But you loved sleeping over at my house because it was quiet with no little sisters,” I said to Mai.

Mai just laughed. “I like a little bit of quiet. But sisters are the best.”

Mercedes twists back and forth in the playground swing. Having Mercedes as a sister—even a half sister—isn’t looking like the best right now.

“Even if you haven’t met him, at least you have his last name,” Mercedes says accusingly. “Gómez.”

“What difference does that make?”

“I have my mom’s last name,” Mercedes says. She’s not looking at me.

“Miller?”

“That’s what happens when your mom isn’t married to your dad.” Her voice is bitter like the white part of a slice of watermelon. “You’re lucky your parents were married.”