At the age you mentioned , she can have either type 1 or 2
diabetes , or maturity onset diabetes of young ( a hereditary condition ) . To differentiate you need the following tests . Importantly , please make sure her sugars are well under control , as such high sugars pose a risk for diabetic ketoacidosis . Please keep proper follow up on her medications and make sure the prescribed insulin is taken in a timely manner .
Next Steps
1. Fasting C peptide levels
2. Anti Gad65 antibody levels