Article continues below advertisementEric Trump appeared visibly uneasy during a tense CNBC interview after being pressed about a reported $500 million investment from an Emirati-backed firm into the Trump family's cryptocurrency venture.Anchor Sara Eisen questioned Eric and his brother Donald Trump Jr. about a deal involving World Liberty Financial - a crypto company co-founded by members of the Trump family and Steve Witkoff, who serves as a special envoy.