"There's one year he snuck off and went down to Alexandria on St. Patrick's Day to have lunch and a pint with people. And they didn't tell anybody. They told the owners of the bar, like, an hour before that the president would show up," he added. The town is just across the Potomac River in Virginia.
Reagan and his sweet tooth - The visit by the Irish prime minister -- when Barack Obama was president, the water in a fountain on the White House lawn was dyed green -- is a chance to celebrate ties between two countries joined by waves of immigration from Irish people fleeing famine in the 19th century.
But it also provides a special diplomatic platform for a country of just five million people, an entree that small nations do not normally enjoy with the world superpower.
In the 1990s Irish leaders took this opportunity to press then president Bill Clinton to help nudge along the peace process in Northern Ireland.
Varadkar is expected to use his time with Trump to address diplomatic issues that include Britain's messy departure from the European Union and its impact on Ireland. The latter is part of the EU while Northern Ireland is in the United Kingdom. Their border is one of the main sticking points in the process.
On a personal level, the two men are very different. Trump is 72 and widely accused of being a white nationalist and anti-immigrant. Varadkar is 40, of partly Indian heritage.
Last year at this time they spoke about the situation of the many Irish living in America.
That came during the shamrock delivery session.
The plant is destroyed, for security reasons, said Costello.
But the president can keep the thing it came in.
Reagan used one such glass pot to hold the jelly beans he was so fond of, said Costello.