Photo taken on May 20, 2021 shows the giant panda cub "Xiao Qi Ji" (little miracle) during a media preview at Smithsonian's National Zoo in Washington, D.C., the United States. Smithsonian's National Zoo will reopen from May 21, 2021. (Photo: Xinhua)

Photo taken on May 20, 2021 shows the giant panda cub "Xiao Qi Ji" (little miracle) during a media preview at Smithsonian's National Zoo in Washington, D.C., the United States. Smithsonian's National Zoo will reopen from May 21, 2021. (Photo: Xinhua)

Photo taken on May 20, 2021 shows the giant panda cub "Xiao Qi Ji" (little miracle) during a media preview at Smithsonian's National Zoo in Washington, D.C., the United States. Smithsonian's National Zoo will reopen from May 21, 2021. (Photo: Xinhua)

Photo taken on May 20, 2021 shows the giant panda cub "Xiao Qi Ji" (little miracle, L) during a media preview at Smithsonian's National Zoo in Washington, D.C., the United States. Smithsonian's National Zoo will reopen from May 21, 2021. (Photo: Xinhua)

Photo taken on May 20, 2021 shows the giant panda cub "Xiao Qi Ji" (little miracle) during a media preview at Smithsonian's National Zoo in Washington, D.C., the United States. Smithsonian's National Zoo will reopen from May 21, 2021. (Photo: Xinhua)

Photo taken on May 20, 2021 shows the giant panda cub "Xiao Qi Ji" (little miracle) during a media preview at Smithsonian's National Zoo in Washington, D.C., the United States. Smithsonian's National Zoo will reopen from May 21, 2021. (Photo: Xinhua)