Are we allowed to perform Mustaab / daily nafal prayers( Namaz e Shab, Daily prayers nafals etc) sitting down with or without any valid excuse. Would we get half the reward? As I heard that nafal or Mustahab prayers can be performed even when you are walking. Could you kindly advise me according to Shareya and my Maraja's Touzeeh. I follow Ayatullah Khamanie.