休戚相关 — “To be closely related and interdependent”

The idiom "休戚相关" (xiū qī xiāng guān) originates from 'Guoyu: Zhou Yu Xia'. During the Spring and Autumn period, Duke Zhou of Jin, also known as Ji Zhou, was a young man who, due to the exclusion by Duke Li of Jin, could not remain in his home state. He resided in Luoyang, then part of the Zhou territory, and worked under Duke Xiang of Zhou.

A high-ranking official of Zhou, Dan Xiangong, held Zhouzi in high regard. He invited Zhouzi to his home and treated him with the utmost respect, like an honored guest. Though young, Zhouzi displayed remarkable maturity and composure. He stood steadily without frivolity, read books with intense focus, listened politely, and always spoke of loyalty, filial piety, benevolence, and righteousness. He was friendly and harmonious in his interactions.

Even while away from his homeland, he worried deeply when he heard of any misfortune befalling Jin and rejoiced greatly at any good news. Dan Xiangong observed all these qualities with satisfaction, convinced that Zhouzi had a promising future and would one day return to Jin to become an excellent ruler. Consequently, Dan Xiangong showed even greater care and affection for Zhouzi.

Not long after, an internal rebellion indeed broke out in Jin, and Duke Li, who had feared losing power and had ostracized the royal princes, was killed. The officials of Jin then sent emissaries to Luoyang to invite Zhouzi back, and he subsequently ascended to the throne as the new ruler of Jin.