We are remodeling our staircase and added a winder at bottom to increase our tread depth. We ended up having to add a 2x12 to the original header where the top of the stringers are attached. The piece of 2x12 hanging down is approximately where the stringer is resting. It is not being supported much, if at all, by the original header. We still need to add a third stringer and finish securing everything. The outer most stringers will also be secured into 2x4 framing for extra support. Do we need to "beef" this up in back for extra support for the stringers or is this sufficient? This was really our only option in order to increase our tread depth unless we added a third winder at the bottom. We really don't want to tear apart and add a third winder. Thanks in advance for advice.