Katherine Schwarzenegger Pratt’s Good Night, Sister Is An Ode To The Magic Of Siblings

When Katherine Schwarzenegger Pratt had the inspiration to write Good Night, Sister (her fifth book and her second for children), she had no idea that her own family would soon resemble the sibling relationship she had growing up and the main characters in her story. “Honestly, what's so crazy is that I started writing the book literally right after I had Lyla,” she tells Romper, referring to her firstborn daughter, now 2 and a half. Schwarzenegger Pratt finished the book right before she got pregnant with her newest baby girl, Eloise. “So I wrote this book about sisters thinking, ‘Oh, it'd be nice if Lyla had a sister, or if the next child that I have is a girl, that'd be really cute.’”

Of course, Schwarzenegger Pratt already knew a thing or two about the ~magic~ of a sister bond. She’s the oldest of Maria Shriver and Arnold Schwarzenegger’s four children — Katherine and Christina, followed by Patrick and Christopher. And now she gets to watch those sibling relationships play out in her own home with her husband, actor, Chris Pratt, their two girls, and her stepson Jack.

From publisher Penguin Young Readers, Good Night Sister very sweetly tells the tale of two little girls — big sister Kat and little sister Tina — who are preparing for their first nights in their own rooms. Kat is moving into a big girl room, and when Tina shares that she’s scared to be without her sister, Kat does her best to share all of her stuffies with her, promising she’ll be OK. But in the end, Tina also gets to be the brave, helpful one, showing that even the little sisters sometimes have to take care of the big sisters. With such fun, happy illustrations by Lucy Fleming, the book really does capture the magic of a shared bedroom and all the little details that go into feeling safe in your own bed at night. Below, Schwarzenegger Pratt shares what it’s like to raise carbon copies of yourself and your best friend, and why Good Night, Sister is so important to her.

So you're the oldest. I have to ask, was Good Night, Sister a story that actually happened? Was this a thing, you and Christina shared a room and then split up rooms?

Actually, we had separate rooms growing up, but we shared rooms a lot just because we always wanted to be together, or we would sleep in each other's room, or we would end up there. But as far as the dynamic between the girls in the book, that is very much so based off the relationship between my sister Christina and I. Because even though I'm the older one, when we were little, I would not do anything without her. I had to have her do everything first. She had to do camp first. She had to go down a slide first. She had to do a sleepover for the very first time.I wanted to write a book — of course about the importance of sisterhood and that relationship — but also just touching on the dynamic between the two of us growing up and really honoring that and celebrating it.

That’s so sweet. I really love this because I have three girls.

Oh, God bless you. Three girls. Woo.

I know. My two older ones are 8 and 4, and they share a room now, but almost every night when I go to check on them, they’re in one another's bed.

So cute. Yeah, so special. The best gift is, of course, any relationship that you have with siblings — it’s incredibly amazing. And then if you don't have that close relationship with your siblings, just being able to have a built-in person in your life that you can have as a playmate growing up, and then that turns into a best friend as you get older. I'm so grateful now as an adult to be able to have such a close relationship with my sister, of course, and also my brothers.

Are you seeing some of that bond already happen with your girls?

For sure, yeah.I didn't really expect to see so many similarities in their dynamic now since they’re so little. But I see so many similarities between the two of them and how Christina and I were when we were little. And even though I don't necessarily remember it, when we go back and watch home movies — which we watch all the time — or even just to see my parents see my girls, they're like, “Oh my gosh, that's the same exact face that you made when you would squeeze Christina, and now Lyla’s doing the same thing.” And, “You guys are already talking about the same thing.” My parents are reminding us, and Christina and I are always just watching the two of them, and we're like, "Oh my gosh, we're going to do this all over again."

So were you hoping you’d have two girls?

Yeah, I come from a big family, so I would definitely love to have a big family in our family as well. So I love that. And it's special to havetwo girls that share a similar age difference as Christina and I, and to just see them together. I didn't find out what I was having both pregnancies, so they were both a surprise.

Oh my gosh.

I know. It's crazy. And for me and my personality, it's so unexpected because I'm such a planner and I like to have all the information, all the details. So to go that many months not knowing what I was going to be welcoming into the world — that was very surprising for so many people. And honestly, including myself. I was like, “Wow, I'm really doing this.” But it was so great. It made the whole birth really exciting, and maybe could have made me probably focus more on the surprise of the child versus the pain of giving birth? Maybe it was distracting. We'll never know.

Does Lyla have a favorite book yet?

We read so many books and she's such a smooth talker that now she'll try to distract me and my husband from bed and she'll be like, "Just one more book, Mommy, just one more book." And I'll be like, "OK, fine. Just one more book." And 10 books later I'm like, "It's 9:00 at night and you're still not asleep. What is going on?"

But she has a couple of favorite books right now. We were reading... gosh, what was the book called? We read a lot over the holidays… A Christmas Tree Owl, which is about an owl that comes to the city in the Rockefeller tree.

s She really loves so many different books. And I hadn't read Good Night, Sister to her because I was kind of like, “Oh, I don't want to make her read my book.” And so I had it out on our kitchen counter because I was packing [one day]. And she was like, “Mommy, can I read this book tonight?" And I was like, "OK, let's read that book.”

So we read it and she's like, “I have that stuffy, that's my stuffy. Why is my stuffy in this book?” At the end I was like, "So what do you think of the book?" She says, “Mommy, it's so cute. This book is so cute. It's so lovely, Mommy.” I was like, “Who are you? But thank you.”

What was your favorite book as a child?

I read Goodnight Moon all the time. My mom actually kept my copy of Goodnight Moon from when I was little, and I now have it in Lyla’s room. So I read it with her and there's half of a page missing, and she's like, “Oh, what happened to this page?” I'm like, “I'm so sorry. I don't know. It's 33 years old.” So I definitely read that a lot growing up. And I was really into horse books and baby books. I loved anything horse related and loved anything that was mommy, child related.

I was also a big baby fan, like the one — oh gosh. The one where she says, “How much I love you?” The name is totally blanking on me. Where she sneaks into his room and rocks him, and then at the end he rocks her?

Oh, um.

Why am I totally blanking at the name of this book?

Wait a minute. Wait a minute. I'm going to tell you right now. It's...

Oh, My Baby You'll Be, right? Or...

Oh, yeah. No, no, no, it's not My Baby You'll Be. Literally, I'm Googling it because I need to know. Because I read that book, my mom read that book with me all the time when I was younger. And she would always be so sad when she would read it and I remember reading it. It's called Love You Forever.

Thank you. There it is.

Yeah, I read that book a lot when I was little, and I remember reading it when I was pregnant with Eloise and I had just moved Lyla into her new room out of the nursery room. And I was reading this book and I was in full “my baby” mode. Full sob, ugly cry, reading this book to her. And she turned around to me and she was like, “You OK, mommy? You OK, mommy?” I was like, “”No, please stay little forever.”