Hi. Thanks for your query. Noted the history about your daughter in law and understood the concerns. Intestinal pain with vomiting for over a year can not be due to flu for sure as this would last for a week or so and not for a year. As per the history this looks to be gastroenteritis of some specific reason for which you need added investigations like Contrast enhanced CT scan of the abdomen an Capsule Endoscopy for small intestines as the Upper GI Endoscopy covers only the esophagus, stomach and 1st part of duodenum. The Colonoscopy covers only the colon and may be small part of the terminal ileum. Specific blood tests and stool tests for three consecutive days can help a lot. One should also opt to see if there are certain foods, additives or beverages that instigate or enhance the problems. Psychogenic cause also needs to be seen and may need a consultation of a Psychiatrist if all the reports are within normal limits and this may be then due to IBS that is irritable bowel syndrome. A course of an antibiotic and metronidazole can be tried of there is an evidence of an infection. Think about other causes like tuberculosis ans such specific diseases. Some patients with Thyrotoxicosis can have the similar problems hence need to check for the thyroid functions.