i have another theory about sharingans. I believe we do not understand the true meaning of an EMS currently. Yes an eternal ms is gained by taking the eye of your brother. However... what if that isn't entirely true?
My theory on EMS. IT MUST BE GIVEN. YES I AM SAYING KAKASHI HAS A FKING EMS NOW. Why? Well EMS is very rare, itachi gave sasuke his eye's that was his plan all along. He was going to LET SASUKE have his eyes. madaras brother died and WANTED his brother madara to have his eyes.... Madara might have been one of the first with EMS? not counting the possibility of indra, but that also goes back to the point. The so6p GAVE his son EMS....
The theory? When a uchiha truly gives away his eyes to the person he truly wants them to be with, they work as an EMS.
My theory on EMS. IT MUST BE GIVEN. YES I AM SAYING KAKASHI HAS A FKING EMS NOW. Why? Well EMS is very rare, itachi gave sasuke his eye's that was his plan all along. He was going to LET SASUKE have his eyes. madaras brother died and WANTED his brother madara to have his eyes.... Madara might have been one of the first with EMS? not counting the possibility of indra, but that also goes back to the point. The so6p GAVE his son EMS....
The theory? When a uchiha truly gives away his eyes to the person he truly wants them to be with, they work as an EMS.