On Thursday, the actor, 67, shared a special shout-out to Fisher, who died two years ago of cardiac arrest. She was 60.
“It makes me so happy to know how overwhelmed & touched she would be by the worldwide outpouring of love & affection for her today,” the Star Wars icon tweeted along with a red heart emoji.
In addition, Hamill added the hashtags #AlwaysWithUs #CarrieOnForever and #KeepMovingThingsAreBoundToBeImproving.
The two starred as twins Luke and Leia through five previous Star Wars films.
Fisher was flying from London to Los Angeles on Dec. 23, 2016, when she went into cardiac arrest. Paramedics removed her from the flight and rushed her to a nearby hospital, where she was treated for a heart attack. She died in the hospital four days later.
In July, Hamill honored Fisher before his return to Star Wars, sharing some of his favorite pictures of his time with Fisher in the previous movies.
“It’s bittersweet facing my final chapter without her-She is simply irreplaceable,” he tweeted. “I’m finding solace in the fact that she won’t BE replaced & would love the worldwide outpouring of affection from those who loved her when they heard the news.”
That same month, Disney and Lucasfilm revealed the official cast list for Star Wars: Episode IX, the ninth trip to a galaxy far, far away, and it contained one major surprise: Fisher, who is back as Leia, will return for the film, thanks to some unused footage shot for Star Wars: The Force Awakens.
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Returning director J.J. Abrams, who co-wrote the script for Episode IX alongside Chris Terrio, said in a statement, “We desperately loved Carrie Fisher. Finding a truly satisfying conclusion to the Skywalker saga without her eluded us. We were never going to recast, or use a CG character. With the support and blessing from her daughter, Billie, we have found a way to honor Carrie’s legacy and role as Leia in Episode IX by using unseen footage we shot together in Episode VII.”
For the one-year anniversary of her death last December, Hamill also used the hashtags #AlwaysWithUs and #CarrieOnForever, writing, “No one’s ever really gone.”
Also on Thursday, Fisher’s beloved dog Gary remembered his owner. “Miss you everyday,” the photo caption of the French bulldog read on Instagram.