They said one of the kids, an American, lived in Ciudad Juarez. So, if he is an American why does he live in Mexico.
Also, the principal of the high school says that 20% of the high school [in the US] live in Mexico.
Because the mexican moms come across the border to have an American baby and then get all the benefits, including schools, SS, food stamps, free healthcare, on and on and on, etc..
Since El Paso and Juarez are like Kansas City Mo and Kan, there could be family split reasons for living in Mexico, cheaper living, or any number of other reasons. (All kinds of American Citizens live in Mexico, BTW, though that may be changing!).
In other words, without any disupting info being turned up, the story may be just what it seems to be.
Simple answer- his mother crossed the border to have him on U.S. soil so he could be a citizen and at any time in his life would be able to take advantage of Uncle Sam. This is very common on the border, that is why so many children from Mexico are allowed to cross and attend school- they are citizens by birth only. Most have never lived here. We really need to end this citizenship process.