EXCLUSIVE: Mark Hamill & the Cast of 'Star Wars' Remember the 'Irreplaceable' Late Carrie Fisher at D23 Expo

Carrie Fisher's castmates are continuing to honor the late legend.

At the D23 Expo this weekend, Fisher's Star Wars: The Last Jedi co-stars spoke to ET's Cameron Mathison about her enduring legacy and the loss they're still feeling.

Mark Hamill told ET, "It's hard to accept you know? I still think of her in the present tense, you know, she's such an irreplaceable part of that legacy."

"But the films were about triumph and tragedy and unfortunately, real life rammed straight into our fantasy in a way that we never could have imagined," he added. "I think the film has an air of melancholy about it, which it doesn't deserve, but that's life, isn't it?"

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Hamill also commented on the similarity between Fisher and her daughter, Billie Lourd, who appeared in the behind-the-scenesLast Jedi teaser released this weekend. "I see so much of Carrie in her that it's just satisfying in a way, I think, for everyone involved in the movie and the public as well to see the legacy passed down from a generation."

Daisy Ridley told ET it was bittersweet knowing Fisher would be missing out on the celebration. "It's hard to sort of summarize what it is, because it's sort of still something that everyone's dealing with. But it's both wonderful and obviously very sad to see the footage, cause you're like, 'Aw that was this incredible thing we did together,' and then obviously she's not there to enjoy it with us."

READ: Billie Lourd ​Pens Touching Speech for Carrie Fisher's Disney Legend Award: ​This Was 'Her Ultimate Dream'

"I think everyone feels it around the world ...all of us and everyone around the world, all the audiences feel it in their own way...because she's part of that legacy," she added. "And also personal ways, because she meant something to everyone away from that. So, it's horrible, it's sad."

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Laura Dern, a Star Wars newcomer who will make her first franchise appearance in The Last Jedi, acknowledged the late star's impact on fans, particularly young women. "Always and forever, not only the icon for all of us for fans of Star Wars...for young girls, for feminism. That she represented one of the first female superheroes of all time but also one of the bravest and boldest and most fiercely hilarious and honest people about herself and her life, and shared her life with us in such beautiful ways. So, getting to be part of a tribute to her and her work and legacy by being a part of Star Wars was amazing."

No doubt Fisher has had an indelible impact on pop culture, something star John Boyega thinks this latest entry into the franchise will highlight appropriately. "I think even before Carrie passed away, I was sure that this was gonna be a movie that would pay her especially, and Mark Hamill, a significant amount of respect for all they've done for the Star Wars franchise. And this was before, you know, anything happened. Now she's passed on, there's even more of a challenge to make sure she is respected and to pay homage to the character that she helped collaborate to create. I'm just excited for her character and I think she would be proud as to how she's represented."

Star Wars: The Last Jedi is due in theaters this Christmas. For more on Carrie Fisher, watch below.