LATEST WHATSAPP FEATURE WILL LET YOU DECIDE FOR GROUP ADMIN
Popular instant messenger—WhatsApp is testing a new feature called “Demote as admin” which will be enable a group administrator to dismiss other administrators without completely kicking or removing them from the group.
If you want to stop someone from being an admin in your group when this feature wasn’t available, I.e before, you must first remove he/she from the group, then re-add him/her, where the person will now be a normal participants.
Now, you won’t go through this stress anymore with the new demote as admin feature, as you can dismiss an admin without removing the person from the group.
Currently available on WhatsApp version 2.18.12 for iOS and Android devices.