Bei Bei climbs over a tree trunk in his enclosure at the Smithsonian National Zoo in Washington on Aug. 24, 2016. Photo: VCG

Bei Bei was born in 2015 to Mei Xiang, who was artificially inseminated. Photo: VCG

An animal keeper presents Bei Bei to the media on Dec. 16, 2015. It was Bei Bei’s first media appearance. Photo: VCG

Bei Bei eats his frozen birthday cake on Aug. 22, 2019. Photo: VCG

Bei Bei sits in a tub eating a carrot. Photo: VCG

Bei Bei makes the trip to China in a special shipping enclosure. Photo: VCG

Bei Bei’s enclosure gets lifted onto a Boeing 777 on Tuesday. The panda was the jumbo jet’s sole passenger. Photo: VCG