男人有大姨夫才公平
[nán rén yŏu dà yí fū cái gōng píng]
In this unique and culturally specific saying, 'Da Yi Fu' is used humorously as it literally refers to one’s wife's brother but here likely alludes jokingly to a concept or situation suggesting fairness only when men have a comparable, supportive relationship in their lives (often interpreted in the light of female support systems)