So you have a big pile of cash. And you will just use it to pay someone to take care of you in your old age. And they will do it lovingly because you paid them. They won't take advantage or even abuse you when you get to the point of not being able to do anything about it yourself.
You're talking about kids as financial investments and they're the irrational ones?
BTW, the average cost of raising a child 0-17 in the US ~$230k. That amount alone sitting in an index fund over many decades will provide for you more than any single person ever could.