Busy Philipps' Child Birdie Channels Claire Foy in 'The Crown' for Halloween — See the Photo!

Busy Philipps/Instagram; Robert Viglasky / Netflix

Busy Philipps' oldest child brought their A-game this Halloween.

The Girls5Eva actress, 43, showed off her 14-year-old child's Halloween costume on Instagram Monday, where Birdie dressed as Claire Foy portraying young Queen Elizabeth II in The Crown.

"Look. All I'm saying is that IF someone wanted to make a show about the making of The Crown, Birdie would make a WONDERFUL Claire Foy," the mom of two captioned the wonderfully moody picture of her child.

Later on, Philipps opened up about how the costume came together in posts shared on her Instagram Story.

"I woke up at 6:30 to do Birdie's hair and spray it brown, which is weirdly harder than I thought it was going to be," she shared. "I think Birdie looked so good."

As for her younger child, Cricket Pearl, 9, Philipps said she "had costume panic" getting ready that morning.

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Busy Philipps/Instagram

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"We didn't get a good picture because she was like, 'I can't go to school in my costume,'" she explained, rolling her eyes as she noted, "But then she did, so."

Philipps also revealed that all the pieces of Birdie's costume were purchased online. "The dress is a vintage dress from Etsy. I just took measurements," she noted, stressing the importance of measurements when buying vintage.

"The crown is from a bridal shop on Etsy and yes it was a crown that Diana wore but it was also, when the Queen was young she wore it as well. The sash I made," she added.

Philipps also gave some more background on Cricket's costume.

"Cricket is Dwight Schrute from The Office, her costume is amazing," the proud mom shared. I bought a little boys suit from sears and [ex Marc Silverstein] found a yellow shirt, a mustard shirt."

busy philipps/Instagram Busy Philipps and Marc Silverstein with their kids

Speaking with PEOPLE last year in partnership with Oui by Yoplait and Essie, in celebration of International Self-Care Day, the mom — who also joked on Instagram that her costume was being an "exhausted woman" — shared how she's teaching her kids about self-care.

"We do different kinds of things. Sometimes my nightly bath becomes a free-for-all in my bathroom. The door is open and my kids come in, sit down and talk to me. It's kind of fun," she shared.

"There's a part of me that could lament that I don't get just alone 'alone time'. But I have to say, I also am very well aware that my kids are getting older and the amount of time that they want to spend with me is getting shorter and shorter. So I will take it wherever I can get it. Sometimes, my kids have their own ideas about the thing is that they want to do."