Normally, alimony awards are always reviewable and modifiable during the time that the alimony order is still in effect, unless the court order in question specifically says otherwise. For background, see http://willicklawgroup.com/spousal-supportalimony/.
Your facts, however, raise the question of whether, as appears would be proper, you have a child support order directly relating to your son for his care after normal emancipation, due to his handicap. If you do not, or you are not sure, please review the background at http://willicklawgroup.com/child-support/, and then consider speaking to a family law specialist.
Actually, you should probably consult with a family law attorney about the alimony matter in any event, to get a specific review of your particular order and to ensure you know exactly what you might do about it, and evaluate your chance of success on any motion you might file. You want to do this as far in advance of the current order expiring as possible.
Answered on Mar 24th, 2015 at 11:21 AM