Can he kiss his seventy-year-old female cousin on the head?
Question

                I have a cousin (daughter of my paternal uncle) who is seventy years old. Is it permissible for me to kiss her on the head over her hijaab or to shake her hand because she is old, or not?
Praise be to Allah.You 
          are not allowed to shake her hand or to kiss her on the head or anywhere 
          else. What is allowed is for you to greet her with words only, even 
          if she is old, because she is not your mahram. There is nothing wrong 
          with you saying, “How are you? How are your children?” etc. The Messenger 
           (peace and blessings of Allaah 
          be upon him) said: “I do not shake hands with women” – and this included 
          old women as well as others. And ‘Aa’ishah (may Allaah be pleased with 
          her) said: “By Allaah, the hand of the Messenger of Allaah never touched 
          the hand of any woman” – meaning women who were not his mahrams, and 
          when he accepted their oaths of allegiance to him, it was by words only.