ANSWER:

As long as you have sincerely repented to Allah while showing deep remorse and stopped doing it completely and advised your sister to stop as well but if she continues to do that you’re not sinful 

Keep giving her dawah from time to time with good manners, knowledge, wisdom, diplomacy and fair preaching as she is committing major shirk that Allah doesn’t forgive if she were to die in such a state. 

QUESTION: I was practicing tarot for 2 years. And I influenced my sister to do so. But, I want to come back to practicing Islam fully. I have asked my sis to stop practicing it and explain the badness about it. But, she doesn’t want to. She even buy tarot again when I dumped her tarot. What should I do for her, Sheikh? I realized that I was wrong and now I’m scared Allah will punish us even more