Hi,
Thanks for posting your query.
Do you have fever/ spasmodic abdominal pain/ acidic belching?
With the available described symptoms, there could be possibility of acute
viral gastroenteritis.
Myalgia is an integral prodromal symptom of viral infection.
You should consult with internal medicine specialist/
pediatrician and should go for thorough check up.
You should also go for
complete blood count,
ultrasound imaging, and serum electrolytes.
Viral infection has also some effect on liver and that's why loss of appetite and fatigue is very common with viral infections.
You should take complete antibiotic therapy, antispasmodics, probiotics, antipyretics.
You should maintain your hydration by taking potassium rich liquids.
Avoid milk and all milk related products.
Your daughter is also likely suffering from the same disease.
Take care,
Dr. Mayank Bhargava