The one who stole the child was not an outsider but one of Commander Rong's comrades—a comrade who had returned from the battlefield, suffering injuries that led to infertility and subsequent mental health issues. His name was Li Jun.
This incident was something Commander Rong and his wife had never disclosed to anyone, including their son Rong Yuan.
Some people accept the reality of losing the ability to have children, while others can't. Li Jun was the latter. Coincidentally, the couple received a letter from his hometown, saying his elderly mother was in poor health and was waiting eagerly to see a grandson.
Li Jun and his wife Hu Lan were revolutionary companions, having braved life-and-death situations together. After their marriage, they hadn't returned home for several years.