不是一家人不进一家门
bù​shì​yī​jiā​rén​bù​jìn​yī​jiā​mén

compatibility

不是一家人不进一家门 (不是一家人不進一家門) bù​shì​yī​jiā​rén​bù​jìn​yī​jiā​mén
compatibility
People who live together as a family or join a specific group often share similar temperaments, habits, or values.
predestination
The belief that becoming family members, especially through marriage, is a result of fate or a predestined connection.

Sources
Definitions
CC-CEDICT