"She is too delish πŸ’•πŸ’•," January Jones commented on the sweet photo of Jessica Simpson's baby girl channeling Old Hollywood glam

By Jen Juneau
Updated September 25, 2020 02:25 PM
Birdie Johnson
| Credit: Jessica Simpson/ Instagram; Amy Sussman/Getty

Diamonds are Birdie Mae's best friend!

On Thursday, Jessica Simpson shared a too-cute snapshot of her 18-month-old daughter channeling Marilyn Monroe in The Seven Year Itch, in which the legendary actress wears a white dress whose skirt billows around her as she stands atop a sidewalk grate over a subway line.

In Birdie's case, the vent cover she stands over is inside her home and her outfit is a little different — a red-and-white polka-dot dress with ruffled sleeves over a diaper, with white buckled shoes to match — but her surprised facial expression couldn't be more perfect for the breezy moment.

"A Marilyn Moment #BIRDIEMAE," Simpson, 40, captioned the photo.

"She is too delish 💕💕," wrote January Jones in a comment.

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Earlier this month, the multi-hyphenate star told PEOPLE that all three of her little ones — Birdie plus son Ace Knute, 7, and daughter Maxwell Drew, 8, all of whom she shares with husband Eric Johnson— are "growing up so fast."

Case in point? How her two older children behave with their younger sibling, who joined the family in March 2019.

"Oh, she is the cutest. Oh my gosh," Simpson said of Birdie. "And it's so cute to watch my older kids with her. My son and her are like BFFs! The cutest. When Birdie is laughing, like cackling, that is a contagious thing throughout the family. Her first word was 'Ace.' "

Simpson added that her "very observant" youngest child "says hi to everybody."

RELATED VIDEO: Jessica Simpson Calls Daughter Birdie Her "Dimple Double" in Adorable Twinning Picture

"She'll stare you down for a bit and then, 'Hi. Hi.' She's so cute," said the doting mom. "She's also a bruiser — she'll just go darting off in one second and you're like, 'Wait, how'd you get all the way over there?' It's crazy. They're growing up so fast."

As for Ace and Maxwell, they're in the thick of their new school year, as Simpson posted a photo on Sept. 1 of the siblings hugging while wearing backpacks on their first day of classes.

"First day of 2nd and 3rd grade for these two kiddos," she captioned the shot of her two oldest children.

The mother of three joked about having tough kids, too. "Ace has a busted lip and Maxi has a busted chin," she wrote. "Finished the summer out strong 😜"