Mandy Moore is engaged -- and she couldn't wait to tell her This Is Us family!
ET's Leanne Aguilera caught up with Chris Sullivan at the This Is Us soundtrack release party, thrown at Jon Huertas' Venice, California, restaurant Clutch Roadhouse on Wednesday, where Sullivan confirmed that Moore was engaged to her musician beau, Taylor Goldsmith -- and revealed that he's already seen the ring!
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"I was just in the studio with her her boyfriend, well now fiance, Taylor. He didn't say a word! He seemed a little effervescent, but he's always pretty effervescent... I know him very well," Sullivan revealed. "He's quickly becoming one of my favorite people, and he and Mandy are an incredible couple."
According to the 37-year-old actor, Moore shared the happy news with her co-stars right away in their Pearson family group chat.
"I've seen the sparkler, but I have not heard the story yet because I have not seen her yet," he explained. "She just sent out an alert over our family text chain, so I can't wait to hear about it."
"She just sent a photo and just wanted us all to know that this just happened, and so then we went on a response spree for about a day and a half," he added. "I'm a huge fan of GIF'ing! I GIF the s**t out of that text chain, and I feel like it's appreciated!"
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Moore's on-screen husband, Huertas, also chimed in on the exciting news.
"I think it's amazing. Good for her. I'm happy for her," he gushed. "Taylor is an amazing guy. I love him so much. I love Mandy so much. I'm really happy that they're going to be joining the club!"
Huertas also offered his best piece of marriage advice: communication.
"You have to talk. You have to communicate with each other and just be honest. I think that's the best thing," he told ET. "If there are troubles, if there are problems, just talk to each other, communicate. You fell in love for a reason -- you can always find that again."
This Is Us: Music From the Series soundtrack drops this Friday, while the show returns Sept. 26 on NBC.
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Find out more about Moore and Goldsmith in the video below.