Another scenario is they select Peggy Duckworth for Veep. We all know Peggy was born in Bangkok from parents that were citizens of Thailand. Nothing in the constitution states you have to be a natural born citizen to be Veep but she could never assume the office of POTUS. Common sense would be that she could not even run for Veep for that mere fact but this is uncommon times and she is a wounded vet which would silence her opposition. Now they stuff the ballot and Uncle Joe has a severe brain fart and cannot assume office. Peggy is not qualified. SanFranNan assumes office for the next four years. That is also an option that most never thought about.
I am pretty sure Tammy Duckworth's father was a U.S. citizen. The issue of natural-born-citizenship of persons born abroad is an interesting one and is not necessarily settled. However, I think her father may have been in Thailand under diplomatic credentials, and if so, I think she is probably a natural born citizen.
Nothing in the constitution states you have to be a natural born citizen to be Veep but she could never assume the office of POTUS.
That is not correct. The last sentence of the 12th Amendment: "But no person constitutionally ineligible to the office of President shall be eligible to that of Vice-President of the United States."
If Tammy Duckworth is not a natural born citizen, then she is not eligible to the office of Vice President.