I'm not going to reveal my 23&me results with my sister
Why would you not tell your sister?
She does not need to know.
I would argue the opposite. You are of the same family and the information would be privy to her to know. She could be curious of the results.
I don't think she cares about the results.
You can tell her you got the results back and ask if she wants to know. If she does not, then you don't share it. But not telling her anything deprives her of that choice.