From China Digital Space
专业孙子 (zhuanye sunzi): professional grandchild
At 39, Mao Xinyu was promoted to the rank of major general in the People's Liberation Army, making him the youngest ever to hold that military title. Skeptical that Mao Xinyu had won the promotion based on his merits, netizens began calling him a "professional grandchild." The term is especially pointed, as "grandchild" in the Beijing dialect can also mean "bastard" or "shameless."
The portly young Mao Xinyu is also famous for his efforts in promoting Mao Zedong thought. He has made several statements that have drawn the scorn of netizens, such as, "What America fears the most is not the modernization of China's army, but the Mao-thought-ification of the army" (美国的学者不怕我们军队的现代化，就怕我们的军队毛泽东思想化). Netizens have also poked fun at his childlike handwriting.