I Will Not Give My Son $3-4

There is the video game my son wants really bad. He has earned/saved enough money to get the game, but not enough to pay the tax. He really bad wants me to give him the extra $3-4 to cover the tax. I know he would pay me back for the amount of the tax, but I am not going to give it to him. It may sound mean, but I am trying to teach him delayed gratification and the joy of being able to buy something entirely on his own. I am also trying to teach him that he can't always rely on Dad to give him "free" money if he needs it. He needs to learn to budget his money wisely, and having Dad, or Mom, give him a little extra, he is not learning the full meaning of saving his money to reach a goal. I know he may be sad now, but he will be much happier when he earns the money on his own and gets his game without having to pay someone else back.