Brown-Vialetto-Van Laere syndrome (BVVLS) is a rare and severe neurometabolic disease. We present two siblings with BVVLS with a novel homozygous mutation in SLC52A3 (formerly C20orf54) gene. The first sibling was admitted with respiratory insufficiency and required mechanical ventilation. After administration of a high dose of riboflavin, all his clinical symptoms were resolved, which also strongly suggested the diagnosis of BVVLS. The second sibling was also found to have the same genetic mutation as her brother. Although she was symptom-free, riboflavin was initiated empirically. On follow-up, she developed no neurologic or metabolic problems with entirely normal growth and development. BVVLS should be considered in the differential diagnosis of unexplained neurologic symptoms such as polyneuropathy and respiratory insufficiency, as BVVLS and multiple acyl-CoA dehydrogenation defect have broadly overlapping symptoms. Furthermore, our cases once again suggest that with proper diagnosis and early high-dose riboflavin treatment, complete reversal of neurologic deficits in BVVLS is possible.