娶你妈的女儿嫁你爸的儿子
[qŭ nĭ mā de nǚ ér jià nĭ bà de ér zi]
Literally translates into 'marry your mom's daughter, wed your dad's son,' suggesting an intertwining relationship (like cousins), or expressing a complicated but close bond with someone; this may often be used colloquially in a humorous or sarcastic context rather than to convey a direct familial connection.