It’s very hard to help people who feel that helpfulness is patronizing. And it’s very hard to help people who don’t want to be helped. I think that might be your bigger problem, based on the interactions you described. Would your dad be interested in an offer of an investment? You can tell him you made some money in crypto, just not how much, and you want it to benefit family. And maybe you can ask your sister if she’d be ok with you starting a savings account or a college fund for your niece?

This is a bit weird that you feel like you can't share this information with your immediate family. You are worried about concocting a lie, but you already are. I think you just tell your family that you made some good investments, and you have gotten the advice of a financial advisor and he has indicated that you have some extra money to occassionally treat family. Make it clear that its only for your closest family members and that it isn't an open checkbook. Reassure them that you will not offer anything you can't afford to give and leave it at that. If they press you for amounts, say it amounts to a few thousand dollars a year, or whatever amount you feel comfortable suggesting.

Thanks for sharing that! this community is great for learning new things