DiGeorge syndrome is a rare congenital anomaly with a wide range of clinical manifestations. This syndrome is usually associated with hypocalcaemia resulting from primary hypoparathyroidism. We report here a case of an 8-year-old boy with partial DiGeorge syndrome who presented initially with neonatal hypocalcaemia, but was subsequently normocalcaemic. Latent hypoparathyroidism was unmasked by a diagnostic EDTA infusion resulting in hypocalcaemia without a parathyroid hormone response. We propose that EDTA infusions can be useful in the diagnosis of latent hypoparathyroidism in children.