Millie Bobby Brown Is Spending ‘Every Second She Can’ with Her Baby Ahead of Their First Christmas Together (Exclusive Source)

Millie Bobby Brown is getting ready to spend the holiday season with her family.

An exclusive source tells PEOPLE that Brown, 21, has been overwhelmed with love for her baby daughter since welcoming her with her husband Jake Bongiovi, 23, this past summer. “Millie is honestly the happiest she’s ever been. Becoming a mom has changed everything for her,” the insider says.

“Even with how crazy her schedule is right now with work and all the Stranger Things promo, she’s with her baby girl every second she can be,” they continue. “She can’t even put into words how much she loves her. She’s really excited for the holidays too, since it’s their first one as a little family.”

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And more kids aren’t out of the question as the source shares that Brown is already considering having a big family.

“Millie has talked about having a big family, so more kids are definitely possible,” they add.

During the red carpet premiere of the last season of Stranger Things in November,  the actress spoke with Entertainment Tonight and revealed that her costar and real-life best friend Noah Schnapp is actually her baby daughter’s godfather.

“Sadie is very, very maternal, but Noah’s her godfather,” Brown said of Sadie Sink and Schnapp. “They all turn into the most gooey, soft versions of themselves [and] their baby voice comes out when they’re around her.”

Schnapp also spoke with the outlet and shared just how excited he is to see his friend step into this new era.

“Aw, it’s honestly the greatest joy,” he said. “It’s actually crazy to me to see her grow from such a wide-eyed, innocent young silly girl and now she’s a mom and married. And I’m just so proud of her.”

In August, Brown and Bongiovi announced they’d welcomed their first baby together via adoption, sharing the news on Instagram. 

“This summer we welcomed our sweet baby girl through adoption. We are beyond excited to embark on this beautiful next chapter of parenthood in both peace and privacy,” she wrote in the post. “And then there were 3.”