Who was expecting to claim the dependency when he applied for the insurance?

• If it was your client, there isn't any way around having your client put the 1095-A on their return.  They might as well claim the brother and at least get the dependent credit.
• If it was the brother, it is an option for your client to not claim the brother as a dependent.  The brother would add the 1095-A to his own tax return (but check the box saying he CAN be claimed as a dependent).  I haven't checked in a while, but I don't think ProSeries will let you do it.  If that is the case, you may need to do massive overrides or manually prepare and file his tax return.