The world’s lightest giant panda cub was born at the Chengdu Research Base of Giant Panda Breeding in China.

At 42.8 gm, the giant panda baby is lighter than an egg, two-thirds the size of, and less than one-fourth the weight of, her twin sister who measured 171.9 gm at birth.

The two babies, who will grow to a weight between 70 and 100 kg, were born to Cheng Da, a resident of the research base in Chengdu, which is the capital of southwest China’s Sichuan Province.

Before the cub’s birth, the world’s lightest panda cub was Wuyi, weighing 51 grams when he was born in 2006 at the Chengdu research base. Wuyi now weighs 132 kg, reported Chinese news agency, Xinhua.