Thank you all for the explanations and direction. This really helped me understand when and where to use legal name versus true name.
I am still doing research on the family name. It is pronounced /ya/-/ne/ (both vowels with macrons, for some reason forum replaces the macron with a ?)or in correlation with English words, yay-knee. The furthest I have been able to go back is from 1791 when my ancestor came from Saxony, Germany to the United States of America. Strangely I believe the family name is a variation of John in German. Other than people I know that is family, the only other time I have seen the name is as a first name in France primarily and once/current French controlled territories and all were females. I can though with much confidence believe that it is an unique family name.
I have been reading tons of posts here and am grateful to have come across this forum. I have been sharing this with my grandfather so it is nice to have someone I can take to and converse about it with.