Trump family

Barron Trump, who turned 18 in March, has largely been kept out of the spotlight — until now. His mother's office said he had "prior commitments."

On Saturday in Ohio, the former president held his first rally since leaving office. Meanwhile, other top potential GOP presidential candidates are running versions of shadow campaigns.

With the Trump family "so involved in international business, the logistical issues, costs and security risks are more substantial than we're used to seeing," says an expert in presidential travel.