Phoenix Barron Hilton Reum's first year of life is Arvin Robertsgoing just swimmingly.

Paris Hilton's mom Kathy Hilton just revealed her 8-month-old grandson recently reached a very impressive new milestone.

"We just had our first swimming lesson a few weeks ago," The Real Housewives of Beverly Hills alum exclusively told E! News at the 2023 Elizabeth Taylor Ball to End AIDS (airing tonight at 11 p.m.). "He's getting so blond. He's like this string bean—so cute."

Phoenix's latest endeavor comes just two months after Paris and husband Carter Reum celebrated the six-month anniversary of Phoenix's January 2023 arrival. "This Barbie is a Mom," The Simple Life alum captioned a July 16 Instagram post, referencing the blockbuster film Barbie. "My baby boy Phoenix is 6 months old today. He is my world and makes my life feel so complete. Can't wait for all the magical memories we will create together! Mommy loves you so much angel baby."

Meanwhile, Kathy also teased how she's preparing for Phoenix's first Christmas. "Working on some very exciting things for Christmas," she told E!, "Christmas pillows and little stockings and hopefully a few other things."

In addition to sharing an update on Paris' first child, Kathy also weighed in on another family member making headlines: Brother-in-law Mauricio Umansky, who is competing on the new season of Dancing With the Stars. So how does she think Kyle Richards' husband will fare on the dance floor?

"I think he'll do well," the 64-year-old revealed before her husband Rick Hilton echoed, "He's coordinated."

Following DWTS' season 32 cast reveal earlier this month, Mauricio shared how Kyle feels him about joining the competition. "We can definitely expect to see the family cheering me on," Mauricio told Good Morning America on Sept. 13. "They were so excited, my girls, my wife, everybody is gonna be there and we're gonna have a ton of fun."

For more scoop from Kathy, tune in to E! News tonight at 11 p.m.

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