Depends. "All happy families are alike; each unhappy family is unhappy in its own way." https://en.wikipedia.org/wiki/Anna_Karenina_principle https://en.wikiped

Depends. "All happy families are alike; each unhappy family is unhappy in its own way." https://en.wikipedia.org/wiki/Anna_Karenina_principle https://en.wikipedia.org/wiki/Anna_Karenina_principle But I think the majority of cases could be covered by these two things: (1) Choose the right person; don't expect that someone will magically change after the kids are born. (2) Don't let your partner feel like a fifth wheel, or rather like a mere money machine, after the kids are born.