Prediction of diabetes in high risk sibs depends on the presence of autoimmune, genetic and metabolic markers.The aim of this study was to identify the sibs at high risk of development TIDM depending on the presence of multiple auto antibodies, HLA DQB1 alleles known to predispose to TIDM as well as reduced FPIR with ultimate goals of prevention of TIDM in these sibs.Multiple islet autoantibody positivity in currently believed to best predict progression to TIDM.A reduced FPIR to intravenous glucose is perceived as a sign of far-advanced deterioration of beta cell function during the development of TIDM.There was no statistically significant difference in FPIR of those with one or two positive antibodies. (P-value > 0.05).We concluded that there is not a practical screening test that is both sensitive and specific to be used in prediabetic persons.