有妹妹的哥哥都是暖男有弟弟的姐姐都是泼妇
[yŏu mèi mèi de gē gē dōu shì nuăn nán yŏu dì dì de jiĕ jiĕ dōu shì pō fù]
'Brothers with younger sisters are warm-hearted men while older sisters with little brothers are temperamental.' It humorously suggests a contrast in gender dynamics within families, hinting at the different roles expected from each.