Jing Zhongxiu held two different attitudes towards Jing Yiran and Jing Yichen in his heart.
That had something to do with their mothers. Zhao Qing had been the only wife whom Jing Zhongxiu ever accepted. He and Zhang Rong were not a real couple. The only reason why he tolerated Zhang Rong for all of these years was because of Jing Yiran's existence. He had made a huge compromise for that son of his.
Jing Zhongxiu had, on many occasions, wanted to kill Zhang Rong so as to take revenge for his wife. But even if Zhang Rong was killed, Zhao Qing could not come back to life. That would also make Jing Yiran motherless and he might hate his whole family while growing up.
However, even though Jing Zhongxiu had allowed Zhang Rong to stay alive, Jing Yiran still hated the Jing Family.
And this kind of hatred reached its peak when Zhang Rong died.