Performed by Ma Li (馬麗) and Zhai Xiaowei (翟孝偉).
The music is composed by San Bao whose work includes the music from the film, "The Road Home", directed by Zhang Yimou. This music is originally from a very popular TV show in China, named Qian Shou (牵手 Hand in Hand).
Note: This film clip is from Youtube: https://www.youtube.com/. The original film clip was from english.cntv.cn (English).