You are kidding yourself if you think thats an actual possibility.
You think their children, who study at U.S. schools, and live their entire lives in the U.S. will still treat Spanish as their mother tongue?
Ah yes, as if Spanish and german americans haven't been influenced or changed by U.S. culture at all.
Ask anyone who was born in the U.S. with an immigrant background if they feel at home in their parents country, chances are they will say no and they will feel like a foreigner there.