Krabbe disease, also known as globoid cell leukodystrophy, is a rare autosomal recessive disorder caused by a deficiency of a lysosomal enzyme, galactocerebrosidase. This defect prevents normal turnover of the galactolipids and results in progressive demyelination. In the infantile form, symptoms typically present at 3 to 6 months of age with subsequent neurologic deterioration. We report a case with presentation on day 7 of life and rapid progression culminating in death at 10 weeks. Galactocerebrosidase activity was absent in the leukocytes, and a 30 kb deletion in the GALC gene was found. To our knowledge, this is the earliest reported death from Krabbe disease. Several family members have multiple sclerosis, which is also a demyelinating disorder. We propose that the neonatal expression could be an example of complementary gene interaction in which coinheritance of a predisposition to multiple sclerosis led to the unusual early manifestation and rapid course of Krabbe disease in this infant.