If Charlie Sheen and Emilio Estevez are brother, why do they have different last names? Is one of them a 'stage name'?
Charlie Sheen is a stage name.
Charlie Sheen (born Carlos Estevez)
is the brother of Emilio Estevez, their Dad being Martin Sheen (but born Ramon <severalmiddlenames> Estevez[1]). So it's not quite so much a stage-name as retaining continuity with his
father's chosen name. (Although I think he's the only one of Sheen/Estevez Sr's kids to have done so.)
For an interesting take on the stage-name/brothers instance... Take Kelly Donovan (born Kelly Donovan Shultz).
Twin brother to Nicholas Brendon Shultz, who reduced this to Nicholas Brendon for his acting career. Nicholas being the actor portraying Xander Harris, of 'Buffy' fame. Kelly has been both an on-screen double (saves on post-production visual doohicky stuff!) and stunt double (for Nicholas in Buffy, and in general for other shows).
(Nothing really to do with the politics that the thread is about, most of which confuses the hell out of us outside of the US. And/or amuses and/or terrifies us. Or at least gives us a few, precious moments of self-superiority until we take a moment to analyse our own politicos, I suspect. But, I suppose if pressed, I'd definitely accept Martin Sheen as POTUS, if he's anything like Bartlett, and I could see a mature Xander Harris filling the role. But not as a Republican, as far as I can surmise.
)
[1] With some accented letters in there, somewhere.