You should tell him at least he had the right to know actually from where and how his Son is earning money for him. I know you might think why but you should tell him maybe it can give happiness to your father that his son is using the educational power he provided to his son to make money. He will be proud of you that his son is having multi-digital skills to stabilize himself financially. If your father understands technology well there are high possibilities that he will join you.
Sometimes it's good to tell our parents about what we do and how we make money. But if they don't know much about investing because of a lack of knowledge, don't tell them how much you have lost at one time. It will only hurt them if you bear a lot of losses even if it will recover in the future.
My father knows everything as he guided me on my initial days about the market and Bitcoin so here I am.
Your dad is a bitcoiner too? Oh wow, that is great, man.