4E Shadows Reborn
Deva are not born per se. All Deva trace their paths back to a specific immortal being that chose to abandon such an existence in the Astral Plane to become active directly in Vitaria. Prohibited from doing so in immortal form by the Pact of Primals, these beings chose to pass into mortality. Once they died, their spirits returned to the Astral, only to be reborn in a new life when their causes once again needed them.
Deva are born fully grown and ready to go to work. Each incarnation is a unique identity, but draws on the knowledge and personalities of those that came before it. Deva are ‘born’ during a primal ritual, in which a druid effectively ‘delivers’ the newly formed Deva from a pod-like cyst that grows on the side of a sacred oak.
The Deva then usually offers service to the primal circle that drew it forth for a period of several years. By then, careful meditation often has revealed the new Deva the purpose for which its previous incarnations have strived. At that point, they may continue that path, or abandon it for their own interests. Note, however, that rumor holds that those Deva that not only abandon their call, but turn against it to evil or avarice risk returning in their next cycle as a rakshasa and will likely never return to immortality.