Billie Lourd Honors Late Mom Carrie Fisher by Dressing Baby Boy Kingston as Princess Leia

Kurt Krieger/Corbis via Getty Images Billie Lourd

Billie Lourd's baby boy is already a fan of his movie-star grandma.

To celebrate the annual Star Wars day May the 4th, the 28-year-old actress honored her late mother Carrie Fisher by dressing her baby boy Kingston Fisher as her character in the sci-fi franchise, Princess Leia. Lourd's son wears a brown knit hat styled like Leia's iconic double-bun hairdo, as well as a white onesie with Leia artwork on it.

"💕♏️🅰️🌱 ✝️♓️📧 4️⃣✝️♓️💕," she captioned the Instagram post, which also showed Kingston watching a laptop screen during one of Fisher's Star Wars scenes. Fisher died in December 2016 at age 60.

Lourd, who appeared in the recent Star Wars trilogy as Kaydel Connix, surprised fans when she announced that she and fiancé Austen Rydell welcomed their first child together in September, sharing a photo of the newborn's feet on Instagram.

Giving rare insight into her pregnancy experience, Lourd joined her stepdad Bruce Bozzi on SiriusXM's Quarantined with Bruce in January. "He's not technically a quarantine baby, and I want to make that known because a lot of people are having trendy quarantine babies," she said at the time. "Kingston was conceived before quarantine. He's technically just a Caribbean baby."

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RELATED: Billie Lourd Shares New Photos of Son Kingston, Calls Fiancé Austen Rydell 'the Best Dad'

Lourd said the pregnancy wasn't planned but it "turned out to be kind of a blessing in disguise having a quarantine baby — but he's not a quarantine baby — because I got to keep it to myself."

"Only my family knew and nobody else knew," she continued, "like everyone was so surprised when we posted that little picture of his feet. It got to just be something I shared with the people I loved the most, which was so incredible and made my pregnancy so magical and wonderful, which I did not expect it was going to be."

Andy Kropa/Getty Billie Lourd and Carrie Fisher in 2011

"But it turned out to be the greatest experience," added Lourd. "I got to just eat great food, hang out with the people I love, do Legos all the time, I took a hypno-birthing class. I loved being pregnant."

"I've wanted to be a mom since I was 2 years old, I always had a plan," she says. "Like, literally when I was 3, I'd tell you, 'I want like four kids. I want like one at 28,' which is so weird 'cause I had Kingston at 28 and it ended up happening, but it's even better than I could have ever expected."

She also shared that Rydell was a good support system throughout her pregnancy. Lourd called him the "best dad in the world."

"He was so caring and incredible and cooked for me and gave me foot massages," she said, adding that he "did these classes with me, like he did the lactation class, he did the positive birthing class. So he was with me every step of the way. And we just became even closer friends, even better partners."