For Donald Trump, the campaign to return to the White House is a family affair. His wife Melania, daughter Ivanka and rest of the family, all scarcely seen with him over the past several months, returned to flank him. Two of his grandchildren sat on his lap and next to him, projecting a soft image of him as a doting grandfather. However, missing from the celebratory scene: the youngest son, 18-year-old Barron.