unresolved hatred
Chinese idiom, Pinyin is B ù Ji ě zh ī ch ó u, which means hatred that can not be relieved. It's from xingshihengyan.
The origin of Idioms
Feng Menglong of Ming Dynasty, the 20th volume of Xingshi Hengyan: "when I saw Zhang Quan buying a house and opening a shop, I found that it was his father-in-law who secretly took his money. He became more and more angry and became an irreconcilable enemy."
Idiom usage
As subject or object; used in spoken English. The Huo and Zhao families had no grudge against each other, but because they didn't admit defeat, they had to fight for each other.
unresolved hatred
from the first small beginnings one can see how things will develop - jiàn wēi zhī zhù
Simple words are few in meaning - yán jiǎn yì shǎo