Hi potty64. I had this very same problem when i was 12 yrs old. mum took me to my then elderly GP who told my mum that he had never heard of a child so young having heartburn, that i had probably overheard adults talking about it and was just attention seeking. More or less accusing me of lying. I am now 32 and have been plagued with stomach complaints since, i was rushed to hospital at 17yrs with an ulcer and have been undergoing different tests and medications for years. My whole life I feel like i've been banging my head against a brick wall until a new doctor joined the surgery and took me more serious than any other doctor ever has. The specialists now think i may have crohns and may have had this, undiagnosed, since childhood. Am just waiting on 1 final test and then we'll know for sure. Hope your granddaughter gets sorted and whatever you do always get a 2nd opinion if you're not happy with the answers you get, it may save her years of misery.