MADRID (AP) — Madrid’s panda family has grown with the birth of twin cubs. The Madrid Zoo announced the births on Monday. The twins were born to their mother, Hua Zuiba, and father, Bing Xing, a pair of giant pandas on loan from China. The births took place with a four-hour difference on Monday morning. Veterinarians were waiting to determine the pair’s sex, weight and vital signs. The statement said the births had been “calmer” due to the mother’s experience. The adult pandas in Madrid have had four other panda cubs previously, including twins in 2010. China’s Chengdu Research Base of Giant Panda Breeding sent two experts for the birth who will help with the first weeks of breastfeeding.