Just start with stretching and hot water fermentation, hi if u can get her to clinic for assessment once.

Primary thing to be done was  get Resourced with VIT D. By taking regular medication as prescribed then exposing to Sun light in the morning hours . The next thing should be giving some rest and hot water fermentation on the site of pain. For gaining long term benefits consult near by Physio learn exercises practice  everyday.

Once she takes enough calcium and vit D3 dosage she will feel better with rheumatoid arthritis medicines.. She can be brought to a physio to recheck if it is a joint inflammation and can be brought down by ultrasound .