Photo taken on Jan 6, 2017 shows the female Yang Yang Panda stay with her twin cubs, female Fu Feng and her brother Fu Ban, in their enclosure at Schoenbrunn Zoo in Vienna, Austria. Twin panda cubs born last summer at Vienna's Schoenbrunn Zoo ventured out of their cave to make their public debut on Dec 30, 2016. The cubs, who still require a lot of sleep, are growing up well, the zoo said. [Photo/IC]