In the state of Wei, the minister Shi Que had his own son, Shi Hou, killed in the state of Chen, because the son had joined the usurper Zhouxu. The Zuo Zhuan comments: “Shi Que was a loyal minister. ‘Destroying kin for the great righteousness,’ that is what it means.”
The idiom 大义灭亲 is still used for a person who does not shield a guilty relative from punishment. It is remembered because it goes against the expected loyalty.