Seroma Under the Armpit, What Treatment is Best when Draining is Not Work? Who Are the Best Doctors for Treatment? (photo)

Ot sounds like she has a seroma that has developed. Often a drain can be placed to help remove the fluid. This may take care of the problem. If not there are other options down the road.  Follow with her surgeon.

Have a drainage system inserted by any general or plastic surgeon in your area. Better yet use the surgeons who did the initial operation. I wonder why the early post birth surgery? 2 weeks seems very early to me??? 

I'm sorry to hear about the complications your daughter has experienced after pregnancy. Based on your description of rapidly recovering seroma, it may be necessary to have a suction drain placed. The drain will serve to continuously evacuate accumulating fluid. Although it is a difficult area to dress, a pressure dressing over the involved area may also be helpful.

Generally, a good general or plastic surgeon will be able to  treat this complication.

Best wishes.