The new mom posted adorable photos with her baby boy wearing a cozy-looking onesie costume to channel the popular ‘Sesame Street’ character

Paris Hilton with her son Phoenix on his first Halloween. PHOTO: PARIS HILTON INSTAGRAM
Paris Hilton celebrated a sweet milestone with her adorable son Phoenix Barron: his first Halloween!

On Tuesday, the new mom posted a series of photos with the 9-month-old dressed up as a popular Sesame Street character, in a cozy-looking red hooded onesie.

“My lil Elmo. 🥹❤️👶🏼❤️,” Hilton, 42, captioned the shots, adding, “#BabysFirstHalloween 🎃.”

Wearing all black and a high ponytail in the shots, Hilton snuggled with Phoenix, who was situated on his mom’s lap. Holding him from behind, Hilton looked down at her son affectionately in one of the snaps as the baby smiled for the camera, which also captured the room’s Chanel sign décor.

“I love my baby boy and my big girl,” the musician and socialite’s mom Kathy Hilton wrote in the comments, with Kris Jenner also stopping by to show love with multiple heart-eye emojis.

Paris Hilton with her son Phoenix on his first Halloween. PARIS HILTON INSTAGRAM

Phoenix’s Elmo outfit is only the latest in a series of Halloween costumes over the past several days, for his first time celebrating the spooky holiday.

For one fit, he dressed as a pilot to match his mom — who wore the iconic outfit from Britney Spears’ 2003 “Toxic” music video. Hilton’s teal Pan Am costume and silver boots were already a hit, but next to her son’s aviator sunglasses, mini pilot’s uniform and black Nikes, she really pulled off the look.

In an earlier post, Hilton channeled yet another pop star and dressed up as Katy Perry, donning the singer’s Las Vegas residency-inspired mushroom fit — with Phoenix in a matching costume!

“Usually I’m preparing my costumes, but I’ve already bought Phoenix probably 20 different costumes,” Hilton told PEOPLE last month leading up to Halloween. “He’s been my focus.”

Detailing that she has costumes that include classic characters such as Elmo, Cookie Monster, Mickey Mouse and Winnie the Pooh, the author also said she had other fun outfits planned for Phoenix, including a unicorn, astronaut, alien and pumpkin, to name a few.

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In July, the proud mom celebrated her son’s half-year birthday.
For the milestone event, Hilton wore a pink heart-print tracksuit as she cuddled Phoenix, whom she shares with husband Carter Reum.

“This Barbie is a Mom. 💕👱🏼‍♀️👶🏼💕,” the mother of one wrote on Instagram. “My baby boy Phoenix is 6 months old today.🥰 He is my world and makes my life feel so complete.🥹”

Added Hilton, “Can’t wait for all the magical memories we will create together!💫 Mommy loves you so much angel baby😇.”