Rumer Willis; Derek Richard Thomas and Rumer Willis at the Los Angeles premiere of “Love ActuallyLive”.Photo:Michael Tullberg/Getty Images; Rumer Willis/Instagram

Rumer Willis and Derek Thomas attend the Los Angeles premiere of “Love Actually Live”

Michael Tullberg/Getty Images; Rumer Willis/Instagram

Rumer Willisis counting down the days until her firstChristmasas a mom!

The actress, who welcomed daughterLouetta Isleywith boyfriendDerek Richard Thomasin April, opened up about her excitement over the upcoming holiday during the opening night ofLove Actually Livein Beverly Hills, California, on Wednesday.

As for festive preparations, the new mom already has them well underway.

“I think I bought little Christmas onesies before she was even born,” Rumer jokes on thered carpetat The Wallis Annenberg Center for the Performing Arts.

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Rumer Willis and daughter Louetta.Rumer Willis Instagram

To my girl, my most precious girl Lou

But little Louetta won’t be the only member of the family sporting a Christmas outfit, as theSorority Rowstar says that the entire extended Willis clan dresses up for the holidays.

“We alwaysdo the matching pajamasevery year, all of us,” Rumer says, adding that she’d love to establish some Christmas traditions of her own now that she’s a mom.

“I love that there’s a possibility of being able to do new traditions as well as carry on the old ones that we’ve already had,” she adds.

Rumer also reveals to PEOPLE how her 7-month-old daughter reminds her of her movie-star father.

Bruce Willis with daughter Rumer Willis and granddaughter Louetta.Rumer Glenn Willis/Instagram

Bruce Willis and Rumer Glenn Willis

Rumer Glenn Willis/Instagram

The oldest child of Bruce, 68, and ex-wifeDemi Moore— who also share daughtersScoutandTallulah Willis— goes on to share that becoming a mom is “incredible.”

“[Louetta] is truly the joy of my life and my little best friend, and I’ve never had anything happen to me that’s brought me greater joy,” Rumer tells PEOPLE.

“✨ Louetta Isley Thomas Willis ✨ You are pure magic 🌱 Born at home on Tuesday, April 18th,” the proud parents wrote alongside a sweetphoto of their newborn daughter. “You are more than we ever dreamed of ✨.”

source: people.com