Some questions:
1. Have you already started the process of sponsoring your parents? If not, then the only course available for you (other than a TRV) is the super-visa. Canada has stopped accepting new applications for sponsoring parents since Nov 2011. The new super visa is applicable only to parents/grandparents and not their dependents (in your case, your brother).
2.If you had already submitted the application prior to Nov 2011, did you include your brother as a dependent? Was he a student at that time too?