Paris Hilton's daughter London is already destined to be a runway model like her mom.

Just ask grandma Kathy Hilton, who recently gave an update on her rapidly growing 4-month-old granddaughter and even shared some adorable new milestones.

"She's beautiful!" The Real Housewives of Beverly Hills alum exclusively told E! News' Francesca Amiker at An Unforgettable Evening benefitting The Women's Cancer Research Fund in L.A. April 10. "She's very long. She's a big, beautiful, happy baby." (For more with Kathy, tune into E! News tonight, April 11, at 11:30 p.m.)

Kathy added that Paris and husband Carter Reum's 15-month-old son Phoenix "loves being a big brother" to their baby girl.

"He pets her like a little puppy and they both have personality," the 65-year-old gushed to E!. "He's dancing and she smiles. Usually a four or five month old, they just lay there and look cute. But she's animated."

Kathy's sweet update comes a day after Paris got candid about keeping her daughter's infancy private—for now, at least.

"I feel like my life has just been so public with everything," The Simple Life alum told E! earlier this week. "So I just wanted to keep my little girl to me. But I'm gonna show her to the world soon ‘cause everyone keeps asking."

The "Stars Are Blind" singer noted she'll reveal the first photo of London to the world "when the time is right."

And, yes, Paris is relishing every moment of being a mother of two under 2 while also considering expanding her family of four.

"I'm having the most incredible time, I've never been happier," the 43-year-old added. "They are the sweetest little angels. But I would love a sister for London because my sister and I have such a close relationship. I don't know, I'm just enjoying them both so much right now. But that would be really amazing."

To get more exclusive scoop from Kathy—including if she plans to return to RHOBH next season—watch E! News tonight, April 11, at 11 p.m. on E!.

And keep reading to see Paris and Carter's sweetest family moments.

The heiress and her son Phoenix appear in a sweet TikTok posted just before New Year's Eve 2023.

After Paris Hilton announced that she and husband Carter Reum welcomed daughter London, she posted this photo of herself and son Phoenix in front of a pink Christmas tree.

She wrote in the caption, "Celebrating our baby girl London with a pink Christmas!"

Paris took Phoenix to Disneyland to celebrate his first Christmas.

"My precious little one, you are more than a dream come true. You make my life complete," Paris wrote on Instagram in January 2024. "Every day with you is a priceless gift, and I’m endlessly grateful to be your mommy." 

Paris and Carter celebrated Phoenix's first Thanksgiving with a giant turkey feast.

Phoenix was already racking up frequent flyer miles before his first birthday.

The Simple Life alum snuggled Phoenix under a Chanel neon light.

The mother-son duo shared a loving glance.

Little Phoenix rocked Burberry for his first trip to New York City.

Nicky Hilton's daughters Lily-Grace Victoria and Theodora "Teddy" Marilyn spent some time with their baby cousin Phoenix.

Paris woke up to Phoenix all dressed up in an adorable chicken beanie on Halloween morning.

Phoenix looked adorable dressed as Elmo for spooky season.

Paris and her son made a splash on Labor Day 2023.

The DJ and Phoenix shared a laugh during a mother-son stroll in the park.

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