It's an expectation and a sacrifice. By having kids you made the choice to make some sacrifices.

In the definition of sacrifice there is no provision for how much you wanted to make said sacrifice or what the motivation was. Simply that you gave one thing up for another thing you found more important.

sacrifice /săk′rə-fīs″/ noun The act of giving up something highly valued for the sake of something else considered to have a greater value or claim. "Social activism often involves tremendous sacrifice."