Barron Trump's brother says he always advises the 18-year-old to be careful because...

"It is rather remarkable that the five of us, that the five kids (Don Jr, Eric, Ivanka, Tiffany, Barron), we are so close and we go out there and fight. And they haven't been able to divide us - and they've tried. They've tried in every way that you can possibly imagine to make it so miserable, so uncomfortable," Eric said. Eric's wife Lara is the chair of the Republican National Committee.