Would you consider a parental relationship to be transactional? There is a huge potential for the relationship to be negative - a child with special needs / medical bills, a child with views so different from yours it causes a huge rift, etc.

What positive return is guaranteed that makes these relationships beneficial? There are plenty of living beings who yeet their young out to live on their own from the start. Or is every parent either throwing away their time/money/effort on a losing transaction?

Is it a gamble for those who are poor, that their children will take care of them? What does that mean for rich people and their children? For extremely wealthy people, who can buy everything they ever need/want, is it solely a gamble that your child will want to spend time with you?