ESH. Yes it'll benefit your son's future, but your wife's son is your son too. You need to realize that giving such a substantial gift to just one son is showing that your family values one child more over the other. Did your step-son receive a christmas gift of comparable value form you of the family?

Based on your post, your step-son doesn't sound like he's a bad kid. Yet he's being punished through exclusion just because he doesn't have his brother's handicap. All you are doing is creating a sense of resentment between you, your son and your step-son by ignoring his feelings over this.

How long have you and your wife been together? Has your family had an opportunity to form any type of relationship with your step-son?