السلام عليكم I am a revert from Italy. I have a non-muslim sister in Germany. She met a shia laymen and now they are together without marriage. What is required from a muslim and what should I do if they come and visit us in Italy?

Ustadh AbdulAziz al-Haqqan

There is nothing on you. You can invite her to Islam and advice if there is use in that and according to wisdom only otherwise nothing is on you.