Blake Lively and Ryan Reynolds Are 'Very Excited About the New Baby,' Says Source: Everyone Has 'Adjusted'

Blake Lively and Ryan Reynolds are being showered with love after becoming a family of six.

"Blake and Ryan are amazing together. Ryan is a great dad. He is very sweet to Blake. They are very excited about the new baby. The older siblings have adjusted great," a source tells PEOPLE.

The couple, who wed in an intimate South Carolina ceremony in September 2012, first announced that they were expecting their fourth child together when Lively, 35, debuted her then-baby bump on the red carpet at the 10th Annual Forbes Power Women's Summit in September.

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On Sunday, she announced that she and her 46-year-old husband had welcomed their new baby through a spirited, Super Bowl-themed Instagram post.

"Puppy Bowl Sunday 2023🥘 🍲 🥧 been busy," wrote Lively next to a carousel of images that revealed she no longer had a baby bump and also featured Reynolds' mother, Tammy.

The new addition joins daughters Betty, 3, Inez, 6, and James, 8.

"Blake is the best mom," adds the source of the mom of four. "She is surrounded by friends that shower her with gifts for all the kids. She and Ryan are a favorite couple. It's a goal for many of Blake's friends to have what she has."

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While the couple has yet to reveal details about the newborn, Reynolds previously expressed on the Today show in November that he hoped the couple's fourth child would be a girl.

"I know girls, so I'm kind of hoping that," the actor said on the morning talk show.

Michael Loccisano/WireImage Blake Lively and Ryan Reynolds

The proud father joked that his preference stems from being one of three brothers. "I love my well-being and my home," he said, teasing that his siblings "were just arsonists and firemen."

Lively also touched on being a girl mom in an interview with Forbes, in which she said being a mom to three daughters has helped her feel comfortable in her skin, personally and professionally.

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"I think having children for me made me feel so much more in my skin," she told the publication in May. "I never felt more myself or at ease in my own body or more confident - not to say that there aren't a bevy of insecurities coming at me a million times a day, but I just feel incredibly settled."

"I just think that growing up, having kids, all of those things made me feel like I only want to do things where I can have really meaningful collaborations and have authorship," Lively continued. "I believe in really valuable collaborations and that's where I'm getting my fulfillment these days and I've never been happier, professionally."