Haley Joel Osment Says He's 'So Grateful' to Have Worked with Bruce Willis on 'The Sixth Sense'

Haley Joel Osment is expressing his "deep admiration" for Bruce Willis.

One day after Willis' family revealed the news that he would be retiring from acting due to his aphasia diagnosis, his Sixth Sense costar Osment posted a tribute to the 67-year-old actor on social media, alongside a dapper black-and-white throwback snapshot of Willis.

"It's been difficult to find the right words for someone I've always looked up to — first on the big screen, and then by some wild stroke of luck, in person," said Osment, who worked as a child star with Willis on the 1999 M. Night Shyamalan supernatural thriller.

The Extremely Wicked, Shockingly Evil and Vile actor, 33, went on to say he considers Willis "a true legend who has enriched all of our lives with a singular career that spans nearly half a century."

"I am so grateful for what I got to witness firsthand, and for the enormous body of work he built for us to enjoy for years and years to come," Osment added. "I just wanted to express the respect and deep admiration I have for Bruce and his family as they move forward with the courage and high spirits that have always defined them."

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Shyamalan, 51, also shared support for the Die Hard star amid his diagnosis reveal, writing in a Wednesday tweet, "All my love and respect to my big brother Bruce Willis. I know his wonderful family is surrounding him with support and strength."

The director added of Willis, "He will always be that hero on that poster on my wall as [a] kid."

Shyamalan and Willis have collaborated multiple times in the past. Willis appeared in multiple films from Shyamalan, including 1999's The Sixth Sense, in which he played Dr. Malcolm Crowe, and 2000's Unbreakable, in which he played David Dunn.

He reprised his role as Dunn in two of Shyamalan's later films, making an uncredited cameo in Split (2016) and playing Dunn again in Glass (2019).

RELATED VIDEO: Bruce Willis Has Aphasia and Is "Stepping Away" from Acting, Family Reveals

Willis' family shared the news of his diagnosis and subsequent retirement on Instagram Wednesday, writing alongside a photo of him on Instagram, "To Bruce's amazing supporters, as a family we wanted to share that our beloved Bruce has been experiencing some health issues and has recently been diagnosed with aphasia, which is impacting his cognitive abilities."

"As a result of this and with much consideration Bruce is stepping away from the career that has meant so much to him," the caption added.

Willis' family's Instagram posts went on to say that it "is a really challenging time" for them all, "and we are so appreciative of your continued love, compassion and support."

"We are moving through this as a strong family unit, and wanted to bring his fans in because we know how much he means to you, as you do to him. As Bruce always says, 'Live it up' and together we plan to do just that," they concluded, signing the note from the actor's daughters Rumer Willis, Scout Willis, Tallulah Willis, Mabel Willis and Evelyn Willis, plus Bruce's wife Emma Heming Willis and his ex-wife Demi Moore.