I was born on 1956, my husband 1951, and our disabled son in 1987. I may not understand our disabled son's benefit but does the software maximize his over my husband's since he is the one who will benefit from his benefit for the longer amount of time?

Loren,
MaximizeMySocialSecurity initially determines your son's disabled child's benefit based on which ever parent files for their retirement benefit first and after both parents file on which ever parent has the highest full retirement age benefit. This ensures that your son gets the maximum benefits possible.
Best,
Mike