What Causes Loose Stools Along With Foul Odour In A Child?

Daughter 8 yrs old is going to the toilet a lot has loose stools foul smelling and has a lot of gas. She is not herself , more tired, less energy, less concentration and sometimes seems very quiet and down. She has also had little patches of a rash (looks like ringworm or something?) she has recently complained that her legs were aching and now her shoulder blades. She has been tested for celiac disease but it's come back negative. She is looking pale and although she hasn't lost weight she is looking smaller and more frail!