Paris Hilton and Kathy Hilton.Photo: Charles Sykes/Bravo/Getty

Paris Hilton, Kathy Hilton

Kathy Hiltonremembers the first time she met her grandson Phoenix Barron Hilton Reum.

“I was in shock, I was incomplete shock,” Kathy toldExtrain an interview published Friday. “We didn’t have our Christmas together because she was working out of the country. [Paris] said, ‘I have a surprise for you,’ and it was my Christmas present. Then she waited a few minutes and goes, ‘I have one more surprise for you.’ "

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US socialite Paris Hilton and her mother Kathy Hilton arrive for the Versace Fall/Winter 2023 fashion show on March 9, 2023, at the Pacific Design Center in West Hollywood, California.

“I thought maybe it’s a puppy because my husband and I lost my dog,” Kathy shared. “Anyway, she walks in, blanket falls down, and I just go, ‘Who is this? What is this?’ "

Since then,Kathy has been “obsessed” with spending time with her grandson, as Paris toldThe Tonight Show Starring Jimmy Fallonearlier this week.

RELATED VIDEO: Paris Hilton Reveals Mom Kathy Hilton Didn’t Know About Son Phoenix Until He Was ‘Over a Week Old’

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“[She’s] obsessed with showing up all the time, unannounced,” Paris joked. “I’m like, ‘Mom, when did you get here?’ ‘Oh, I’ve been here for hours!’ "

Kathy also toldExtraof her grandson, “He is such a little angel,” adding that he is “getting heavy and heavier every few days.”

The Hilton matriarch previously told PEOPLE exclusively that she andhusband Rick Hilton"are over the moon” after the birth of their grandson.

“Paris and Carter, we know you are going to be the most amazing parents,” Kathy said in a statement to PEOPLE. “We are so thrilled for you both! Thank you for this perfect addition to our ever-growing, beautiful family.”

source: people.com