The '13: The Musical' actor spoke with ET about his friend's new book, as well as expanding his family and his new Netflix project.
Peck recently spoke with ET's Denny Directo, while promoting his new Netflix coming-of-age dramedy 13: The Musical, and he opened up about the iCarly actress' tell-all, I'm Glad My Mom Died.
"I just think it's incredibly brave," Peck said of the memoir. "And for her to do it in a way [where] she has this beautifully biting comedic voice and this thoughtful way of expressing her journey and her pain and her challenge."
"I just honor her in that because it takes a lot of guts," he added. "But I also know sort of the power, that when you do get vulnerable and share your story, how so many people can see themselves in it and find a little bit of a reprieve, so I'm just really proud of her."
In her new memoir, the 30-year-old former actress details the emotional and physical abuse she says she endured throughout her childhood up until her mom's 2013 death from cancer. She also reflected on her professional challenges and experiences growing up under the heat of the public spotlight.
Peck -- who wrote a memoir of his own, Happy People Are Annoying, published earlier this year -- said he related a lot to McCurdy's story of early fame.
"Navigating, sort of, growing up in the public eye, your not always afforded sort of the opportunity to stumble in a safe way that you would be if you were just having a normal kid experience," Peck explained, adding that one of the biggest issues facing young actors is a lot of "extra pressure."
Meanwhile, Peck, now 35, has grown up and navigated his way to adulthood amid fame. The actor has been married since 2017 to Paige O'Brien. The couple share a 3-year-old son, Max, and are expecting their second child.
When asked how the pair are getting ready for the new addition, Peck joked, "I think, you know, we're moving to a bigger place and so we are hardcore adulting. Like oh my, we own property!"
"It's fabulous. I mean, I always say having a kid is the one thing that’s not overrated in life. It's not overhyped," Peck added with a smile.
On top of his growing family, Peck also has a lot on his plate career-wise. Peck confirmed that he'll be returning for the second season of How I Met Your Father.
"Maybe I'll get in trouble after I leave here for confirming, but yeah," Peck said with a laugh. "Hilary [Duff] is a dream and I feel lucky to be her friend. I've known her for over 10 years and just the entire group there, all the actors, the creator, it's a beautiful time. I'm so lucky to be a part of it."
Additionally, Peck is appearing in the new Netflix dramedy 13: The Musical. The story follows a middle schooler named Evan Goldman (Eli Golden), who moves from New York City to a small town in Indiana following his parents' divorce. He is determined to throw the best bar mitzvah ever, and Peck stars as Evan's rabbi who will oversee the event.
"I love the idea that we're sort of redefining this idea of sort of a stately stoic sort of long-bearded religious leader into this kind of cool millennial rabbi who's trying to help this kid, who very clearly is going through it," Peck shared. "His parents are recently divorced he's recently uprooted his life from New York City, so there's a bit of a culture shock... And [I'm] just trying to help him throughout this process because bar mitzvahs are wonderful and weird and challenging, and I think my character really knows that."
13: The Musical -- adapted from Jason Robert Brown and Dan Elish's 2007 musical -- is streaming now on Netflix.
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