Can a /Naturopathy/Dietion help My sister?P give her diet plan f calcium?

My English is not well.I am 29yrs lady.My sister cannot walk due to strong knee pain. knee Xray is normal.But bone doctor tell one day bone is shrink.Another day he told us there is calcium deficiency.What is the fact?IShe is 29yrs lady.Height 4.11.weight 63.How which calcium will requiry for her?Dietion p give diet plan..She cannot digest milk ,egg and chicken .She get diarrhea due to said food.understand.What is difference yogurd and curd.?