P.L.
My daughter has cerebral palsy and I understand about the worry of their development. I don't have advice as far as the brace but one of the best things I did for my daughter was to find our local Infant Program. It really depends on each area as to what it is named but you can usually find it thru your local Health Department or Mental Health Department. It is called Early Intervention and they help with physical therapy, occupational therapy and other therapys you may not need. I also found it a great way to meet other parents in the program. My daughter is now 14 and I am still friends with parents I met when she was 6 mths old.
Your daughter may be delayed in walking but the therapist will give you things to do to get her ready to walk once the doctor says it is OK for her to start trying. He may want to wait on her walking until her hip is ready. I know how it breaks your heart that she may not do things at the normal pace but you also don't want things to cause her pain. My daughter had to have hip surgery at 5 because her hip came out of joint due to muscle tone from the cerebral palsy. Not an easy thing to go thru but she always jumps back very fast. I think faster than my heart does. Good luck and I will keep you in my prayers.