Sexual attraction or arousal towards a close family member, such as a sister, is considered taboo and socially unacceptable in most cultures. It is not considered normal or healthy to be sexually attracted to a sibling or any close family member.
The phenomenon of being sexually attracted to family members is known as "genetic sexual attraction" (GSA), and it can occur in certain circumstances, especially if family members have been separated during early childhood and are reunited later in life. However, even in such cases, acting on these feelings is generally considered inappropriate and is often illegal in many jurisdictions.
It's important to recognize that such feelings can be distressing and complicated for those experiencing them. If you find yourself struggling with such emotions, it is essential to seek professional help from a therapist or counselor who specializes in dealing with complex emotional issues.
Remember, open communication and seeking support from mental health professionals can aid in understanding and addressing the underlying causes of such feelings, allowing you to develop healthy and appropriate relationships with your family members.