OK, understand, most members of polytheistic pantheons have no fixed "roles" - they are gods, they can do
anything. What people asked them for changed, and their stories evolved, over time. Frequently several gods were venerated for the same thing at he same time and who people prayed to for what depended more on the popular stories and word of mouth referrals than anything inherent to the deity. It usually didn't hurt to pray to more than one for the same thing, just to hedge your bets.
Even deities that began as personifications of nature gain more attributes as stories are told about them.
Isis displaced
Hathor to some extent, and
Hathor before her displaced other deities. There is no canonical work, no orthodoxy except what suited the Pharaohs and priests. The origins and roles of these gods were retconned over and over again, by priests, bards, poets, and political spin-masters.