The site of the true bottomless financial pit is the toy store. It's amazing how much a few pieces of plastic and paper will sell for if the purchasers are parents or grandparent, especially when the manufacturers claim their product improves a child's intellectual or physical development.
Our species successfully raised children for tens of thousands of years before the first person wrote down the word "psychology." The fundamental skills needed to be a parent are within us. All we're really doing is fine-tuning a process that's already remarkably successful.
It's important to remember that children who are facing a frightening situation have three fundamental concerns: Am I safe? Are you, the people who care for me, safe? How will this affect my daily life?