一家人不说两家话 一家人不說兩家話

    yījiārénbùshuōliǎngjiāhuà

    1. Idiomliterally family members speak frankly with one another, not courteously, as if they were from two different families (idiom); figuratively people don't need to be deferential when they ask a family member for help
    2. people from the same family should stick together (and good friends likewise)