Shaking hands with the sister-in-law

Q: Is it permissible for me to shake hands with my sister-in-law? We were raised together, and now we live in the same house. Can I also stay up late with her or talk to her? Please advise, May Allah benefit you and reward you with the best.

A: It is impermissible for you to shake hands with your sister-in-law or stay up late with her. You can only greet her verbally and talk to her without Khulwah (being alone with a member of the opposite sex), according to necessity, when there is no fear of Fitnah (temptation). May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.