Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)

Sijia plays at Giant Panda House in the ski resort of Yabuli, northeast China's Heilongjiang Province, Aug. 12, 2019. Giant panda Sijia, born in 2006, moved to Yabuli in July 2016 from southwest China's Sichuan Province. The panda house celebrated Sijia's 13th birthday on Monday. (Xinhua/Wang Song)