Hilton, 42, who recently welcomed her first child via surrogate, a son called Phoenix Barron Hilton Reum, said she was “so excited” for Lohan in a recent interview.
“I just feel so happy for her and it’s just exciting to see all of my friends growing up and starting families of their own, and my advice is just to soak in every moment. It’s just so precious,” Hilton told Access Hollywood.
“Everyone is just saying they grow so fast. So just to enjoy the little baby moments when we’re just, like, snuggling and he’s just a little, tiny angel.”
Mean Girls star Lohan, 36, announced that she and her husband Bader Shammas, also 36, are expecting their first child in a post on Instagram on Tuesday.
“We are blessed and excited,” Lohan captioned an image of a baby onesie with the text “coming soon” printed on it.
Hilton was quick to comment on Lohan’s Instagram post, writing: “Congratulations love! So happy for you. Welcome to the Mummy Club!”
Hilton previously revealed that her son’s name was inspired by her own moniker. Writing in her new memoir, titled Paris: The Memoir, Hilton said that she decided on the name “years ago” when she was looking at a map for names of “cities, countries, and states to go with Paris and London”.
The heiress has previously stated that, if she were to have a daughter, she would like to call her London.
Her son’s middle name, Barron, came from her grandfather, Barron Hilton.
“We were so close and I miss him everyday,” she said. “So I really wanted to honour him by having his name in my first son's name.”
Watch: Paris Hilton admits grandma Kathy is 'obsessed' with baby Phoenix