Hi. Thanks for your query. Noted the history and understood the concerns. The commonest cause of pain in abdomen in a child of 4 years, particularly in the evening for 2 weeks and vomiting 4 times in spite of visits to GPs and hospital CA be one of the following: Worms in intestine. Abdominal lymph node inflammation. Intolerance to certain foods or beverages. Appendicitis. Hence it is important for proper clinical evaluation by a General Surgeon or a Pediatric Surgeon and supportive investigations as follows: High resolution ultrasound. Tests of blood, urine and stool. Trial with an antibiotic, deworming and probiotics. This will give final proper diagnosis and plan for treatment.