Chadwick Boseman kept his colon cancer a secret because he was a “very private” person, according to two people who knew him best.

In a new profile from The Hollywood Reporter, the late actor’s longtime agent, Michael Greene, and trainer, Addison Henderson, opened up about his private cancer battle.

Boseman succumbed to the disease on Friday.

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In an intimate reveal, Greene said the actor’s mother “always taught him not to have people fuss over him.” He also added, “[Boseman] also felt in this business that people trip out about things, and he was a very, very private person.”

While no one knew it, Boseman was “really in hardcore pain” while filming the upcoming Netflix movie “Ma Rainey’s Black Bottom” co-starring Viola Davis. Denzel Washington served as a producer on the project.

And according to Henderson, Boseman “was just living his artistic life to the fullest and using his time and his moment to really affect people.”

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“For us, it was just like, ‘Let’s keep going, let’s keep doing what you want to do, let’s keep training,'” he added. “Chad had so much wisdom, so much knowledge, so much inside of him that he wasn’t going to let this disease stop him from telling these amazing stories and showing his art in the prime of his life.”

No word on when “Ma Rainey’s Black Bottom” will be released.