Bryan Caplan... says that a child is helped the most if they are in a positive atmosphere.Here's his book: "Selfish Reasons to Have More Kids: Why Being a Great Parent is Less Work and More Fun Than You Think." There's a big excerpt from the book at the first link, including:
And if they follow that step, Caplan says, parents can relax — and focus on having even more children. Caplan, who teaches at George Mason University, has three children himself — twin 8-year-olds and an infant.
Children cost far less than most parents pay, because parents overcharge themselves. You can have an independent life and still be an admirable parent. Before you decide against another child, then, you owe it to yourself to reconsider. If your sacrifice is only a fraction of what you originally thought, the kid might be a good deal after all.