U.S. House Speaker Paul Ryan (left) listens to Bridgette Harrington (right) recite a poem before the lighting of the U.S. Capitol Christmas Tree on the building's West Front Lawn in Washington D.C. on Thursday, December 6, 2018. [Photo: IC]"

The U.S. Capitol Christmas Tree following a lighting ceremony on Capitol Hill in Washington D.C. on Thursday, December 6, 2018. The noble fir from Oregon traveled almost 5,000 kilometers through a dozen states on its journey to the nation's capital. [Photo: VCG]"

Liam Fitzsimmons with his daughter Janie, aged three, attend the Capitol Christmas Tree lighting ceremony on the West Front Lawn of the U.S. Capitol in Washington, U.S., December 6, 2018. [Photo: VCG]"

Visitors photograph the U.S. Capitol Christmas Tree, also known as the "People's Tree", following a lighting ceremony on Capitol Hill in Washington D.C. on Thursday, December 6, 2018. [Photo: VCG]"

The U.S. Capitol Christmas Tree following a lighting ceremony on Capitol Hill in Washington D.C. on Thursday, December 6, 2018. The noble fir from Oregon traveled almost 5,000 kilometers through a dozen states on its journey to the nation's capital. [Photo: VCG]"