No, they aren't your 'sisters'. Dothey believe that Jesus is the Savior or the world as the Bible teaches? They the Muslims, don't the Jewish ppl don't etc? Then they are in NO WAY 'sisters' of yours since they are of another spirit. God even. And they are technically 'anti0christ'. Do you think Jesus is calling anti christ 'brother or sister' or 'saved'? No, he is not. But they, the anti christ/s' are always welcome to repent and come to an accurate understanding of Jesus and 'be saved' and become 'sisters' and for men 'brothers' in Christ. Thank you.