In RETURN OF THE CONDOR HEROES, you can't help but get the feeling that Gwok Jing loved Yeung Gor more than he did his own biological offspring. Gwok Jing loved Gwok Fu, but not enough to spare cutting off her arm after he found out that she had severed Yeung Gor's arm. When Gwok Seung had been kidnapped by Lee Mok Sau, Gwok Jing was more worried about saving Yeung Gor from the Passion Flower Poison than about rescuing his newborn daughter from a vicious killer. When 16-year old Gwok Seung was held hostage by the Golden Wheel Monk outside of Seung Yeung Fortress, Gwok Jing was again more concerned about Yeung Gor (who was believed to be missing in action at Passionless Valley, although in truth, he was en rout to Seung Yeung at the time with Little Dragon Girl and the Divine Condor).
What is the reason for Gwok Jing's apparent greater love for this adopted "son" than for his own biological children? It's not that Gwok Jing is prejudiced against female offspring (as has long been the case in Chinese culture), because he didn't show Gwok Por Lo the same affection that he showed Yeung Gor. Was it mainly guilt over what happened to Yeung Hong? A sense of responsibility to Yeung Teet Sum?