[SauronOfMordor]

The same way we handle polygamy from the middle east or africa. The first wife is recognized the second, third, and fourth are not. (had a case with this issue)

How about marriages where the wife is younger than eligible marriage age in any of the 50 US states (Mohammad's 9-year-old bride comes to mind)?

[reg45]

How about marriages where the wife is younger than eligible marriage age in any of the 50 US states?

That's simple, the marriage would not be recognized UNTIL the underage person reached the age of eligibility.