Of course they can’t be; however, only you and I know about this fact, on all of FR, it seems.
Technically, Cheney should not have been Dubya’s running mate in 2000, as they were both residents of Texas, and Cheney had to scramble to change his residency back to Wyoming (which he hadn’t really resided in since he left Congress a decade earlier).
If Trump wants to groom his children for the Presidency, he needs to urge them to run for Governor or Senator from different states (NY and CA).