Also, since Khan's followers in ST2:TWoK are a phenotypically uniform lot of young kids, it stands to reason that they are all children of the Alpha Male and his principal wife...
The question then becomes, was the mother McGivers
Um...no. Even though Khan's followers looked young, none of them were born on the planet.
TERRELL: What do you want with us? Sir, I demand...
KHAN: You are in a position to demand nothing, sir. I, on the other hand, am in a position to grant ...nothing. What you see is all that remains of the ship's company and crew of the Botany Bay, marooned here fifteen years ago by Captain James T. Kirk.
TERRELL: Listen, you men and women, you have a...
KHAN: Captain! Captain! Save your strength. These people have sworn to live and die at my command two hundred years before you were born.
This is an odd case, where the screenplay and the casting don't seem to be on the same page. Yes, the dialogue implies that these are same Botany Bay
superhumans we saw in "Space Seed," but they look completely different and clearly appear to be at least a generation younger than Khan.
The dialogue says one thing, but the visuals say something else. We have an aged Khan surrounded by a tribe of young, feral-looking Augments . . . .
(Indeed, as I mentioned before, at least one of the actors--Judson Scott--was under the impression that he was playing Khan's son while the movie was being filmed.)
In writing the book, I decided that what we actually saw on screen trumped a couple incongruous lines of dialogue and established that a second generation of superhumans was born during Khan's exile. The way I rationalized it, Khan was just indulging in a bit of poetic license when he was speaking to Chekov and Terrell, or perhaps, after fifteen years in hell, he was a trifle deranged at that point . . . .