The gifts you buy children can leave a powerful positive or negative mark on their self-esteem, Grover says. That can happen in two ways. The first kind of self-esteem builder, her says, is “transient” and based on materialism. In gift speak, this means products like sneakers or a brand new phone that a kid thinks will make them more popular among their friends and classmates. But gifts that make a child feel accepted externally and maybe not internally can be problematic—and can build dependency on materialism. After all, the sneakers will go out of style, and a newer, fancier phone will be released in a couple months. When that happens, Grover says, we’re back to square one.