Uchiha Clan and There EMS.
If an uchiha got an EMS, couldn't he give he switch his eyes with his son when he retires of being a shinobi.
He could give it to his son when his son is about the age of 10-15.
The father will not be blind because his switched his sharingan with his son, so his son gets the EMS and he gets the 3-Tomoe
The son could use the EMS when he has enough chakra to use it.
The son will also not be like kakashi, the son would be able to deactivate his sharingan.
And the EMS will not lose its light like the MS.
Then hopefully if the son doesn't die, he could switch eyes with his son and so on
This is a great way of obtaining EMS, rather than killing the person closest to you and taking the eyes your brothers eyes.
Just thought of it now hehe :D