my sister has been diagnose to have a childhood gastritis she always feel nausious and she always feels abdominal pain and about 2 days ago ived noticed that she has a puss on the side of her throat now she has difficulty swallowing i need a piece of advice on how to at least help her ease the pain that shes goin through by the way she's 8 years old any advise would be a great help for me thank you in advance