Rachel McAdams is Charles Langstonrocking the role of cool mom both on and offscreen.

The actress portrays the protagonist's mother in the upcoming film adaptation of Judy Blume's iconic novel Are You There God? It's Me, Margaret. It marks the second time Rachel, who shares a 5-year-old son and 2-year-old daughter with partner Jamie Linden, has played a mom since she became one in real life. (Her character has a baby at the end of 2020's Eurovision Song Contest: The Story of Fire Saga.)

"It's great to play a mom as a mom," the Mean Girls star exclusively told E! News. "I've played moms before in the past for probably the last decade. But it's a different experience when you have done it in your real life, too."

Rachel continued, "It was great to bring that in. You don't have to work as hard or be as nervous about not understanding it. I always hope to play all kinds of different characters and playing a mom is a real privilege."

Are You There God? It's Me, Margaret depicts the coming-of-age story of Margaret Simon, played by Ant-Man and the Wasp star Abby Ryder Fortson. Rachel identifies with both her character, Barbara Simon, and with the pre-teen.

"Oh gosh, I feel like it changes day to day," the actress said. "Some days I'm like, 'Oh god, I feel like I'm 12 years old and I don't know what's happening.' And then other days you're like, 'Oh my god, I'm 44 and I still don't know what's happening.' And then you have these, like, quiet moments of feeling like, 'OK, it's all going to be alright.' So, it's just a constant journey, isn't it?"

Are You There God? It's Me, Margaret is set to be released in theaters April 28. To learn author Judy Blume's thoughts on the movie, click here.

For the latest breaking news updates, click here to download the E! News App