[El Gato]

The Constitution says nothing about the right of consenting adults to marry, yet there is no doubt that the right exists.

Indeed it does, and it's protected from governmental infringement by both the 9th and 10th amendments. When the Constitution and Bill of Rights were written, marriage was not a concern of government at least not of legislautres. It was a concern mainly of the churches, and secondarily of the courts. Hence "common law marriage", which is marriage outside both church and state.

The same is true of birth records. Those were strictly private and church business until much more recently than the late 1700s.

[Democratic_Machiavelli]

You're right. I do genealogy as a hobby, and most birth certificates (state-issued) don't exist until around the late 1800's if you're lucky...1900-10 if you're not.