How Is Divalproex Different From Depakote?

within the manufacturers warning information for depakote a death related to diabetes was called out so Lamictal was recommended. Lamictal has never prevented or stopped my son from having seizures so now neurology is adding divalproex. How is this different from depakote? Why should I continue this regimen path when endocrinology would never prescibe anti-seizure meds?