I heard the voice coming from my father -in -law's room. He still loved his deceased wife, and was a clumsy but reliable father -in -law. My father -in -law often masturbates and I often come across that, what should I do?

I heard the voice coming from my father -in -law's room. He still loved his deceased wife, and was a clumsy but reliable father -in -law. My father -in -law often masturbates and I often come across that, what should I do?