With such an elevated blood sugar it is possible that your daughter is diabetic. Type 2 diabetes
has a strong genetic component and this is a factor that might increase her risk of diabetes.
However, I assume that you measured your daughter's blood sugar while fasting, because if you measured it right after she ate then this blood sugar level tells nothing about diabetes.
When we eat food our blood sugar typically increases way beyond normal levels, but it than goes back shortly after due to insulin
secretion and action.
The fact that your daughter drinks a lot and is eating rather a lot, together with elevated blood sugar, might indicate the presence of diabetes.
To be completely sure you need to measure fast blood glucose
levels and 2-hour postprandial glucose levels. Please talk to your doctor as soon as you can.
Hope I have answered your query. Let me know if I can assist you further.
Dr Ervin Toçi, General & Family Physician