Director Sun truly had an everlasting sense of gratitude towards the Zhang Family.
Back in the day, this fellow was dirt-poor, received his benefaction from Grandpa Zhang Hongyang, was nurtured all the way, and eventually grew into his current stature.
At the same time, Director Sun's wife was also the niece of Zhang Hongyang's grandmother, which meant he had thoroughly integrated into the Zhang Family System.
Before Zhang Hongyang arrived, he had already thought things through very thoroughly.
When Zhang Hongyang met Uncle Sun, he felt somewhat awkward but also very self-reproachful and regretful. He blamed Liu Zhizhong for calling and provoking him so much that he lost control of his emotions in the heat of the moment, and he hadn't anticipated such severe consequences.