It pains Sylvester Stallone to see his friend and former co-star Bruce Willis in poor health.

It was reported in March that Willis is stepping away from his acting career after being diagnosed with Aphasia. It is a disorder that affects the ability to communicate, affecting speech, writing and language.

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Stallone, in a new interview, revealed that he has not been in contact with Willis recently but that it pains him to hear about Willis’ health.

“Bruce is going through some really, really difficult times,” Stallone recently told The Hollywood Reporter. “So he’s been sort of incommunicado. That kills me. It’s so sad.”

Stallone first opened up about Willis’ diagnoses in March. The “Rocky” superstar expressed his well wishes for the Willis family in an Instagram post.

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“We go back a long way, praying for the best for you and your wonderful family,” Stallone wrote at the time.

Stallone and Willis starred opposite each other in the 2010s “Expendables” movie franchise. They also had a hand in launching the Planet Hollywood themed restaurant chain along with Arnold Schwarzenegger and Demi Moore.