"I did tell Dan before I told most of my family, just because I wanted him to know in preparation for writing the season what to sort of expect," Moore, 36, told reporters on a virtual panel on Friday afternoon. "Oddly, I was nervous. I don’t know why because I know you Dan. But it was the loveliest exchange and conversation."
While Moore may have had some nerves telling Fogelman about her expanding family, he shared that her pregnancy didn't force them to make major changes to their season 5 plans.
"From my perspective, I was just happy for Mandy. And so, yeah, we haven’t really adjusted our plan. We’re just going to work Mandy right ‘til go time," Fogelman said with a chuckle. "Amongst the many challenges of this season of production, that’s not a big one. We are so far ahead in scripts that we can compensate for things as need be. Because our timelines are so split and because we live in so many timelines, there may be a brief period and window where you don’t see a lot of old Rebecca on the show because she would have some really complicated explaining to do. But other than that, we’re going to be sticking with the plan and we couldn’t be happier for Mandy."
Moore's co-stars couldn't be happier to welcome her into motherhood. Milo Ventimiglia and Chrissy Metz found out the baby news on a cast call ahead of the new season.
"I'm so excited. I'm so excited for her," Ventimiglia, 43, told ET's Nischelle Turner on Friday. "When she told the group of us, we were all on a call talking about some stuff preseason. It was Dan and the whole cast and then Dan hopped off and she told all of us the news. It's wonderful news. You get excited about that. Mandy and Taylor, her husband, they are just the best people. They are the kind of folks who should be parents."
"You would’ve thought that I was having the child. I was so excited, I cried!" Metz, 40, told ET of her reaction. "When you love someone and they tell you, it's different if it's family or a friend, but when she told us, I was like, 'Oh my gosh!' Like, I just know how much her and Taylor want to have a family and so it's really beautiful to see someone [get that] and I know that they're going to be the best parents... I'm just really happy for them 'cause I know how happy they are."
"Mandy gets to go back and forth in time, luckily she's pregnant sometimes and so she can kind of cover up her belly," she said of how the show will work around her growing belly. "The other day we were sitting on set and I was like, 'Mandy, you're making a human being right now,' and she's like, 'I know!' You don't think about it 'cause you're so in the scene and I'm like, 'Wait she's making a baby!' They've done a brilliant job of working around it. I don't know how, I guess it'll be magic."
This Is Usreturns with a two-hour premiere Tuesday, Oct. 27 at 9 p.m. ET/PT on NBC.
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