Leg swelling has various reasons including joint problems, diabetes, hypothyroidism, heart failure, kidney or liver problems etc. More information is needed to understand the cause properly. Is there any specific joint pain along with the swelling? Is she having shortness of breath during walking or climbing stairs? Is she having inadequate urine production? All this questions point to different causes of leg swelling. Kindly give more information regarding her present problems and past medical history. A General physician would be best suited for her.