The demigods are immortal individuals that protect our reality from eldritch abominations, such as Cthulu, Niggurath, etc, on a plane that exists between our world and theirs. These battles against these eldritch forces and their minions happen on a daily basis to prevent them from breaching our world. A demigod is born with a divine spark in their soul, which matures as they age and blooms around puberty (9 - 16 yrs), when it reveals itself. This is a rare event around the world, with individuals being born sometimes many generations apart.
After the revelation, a process begins which concludes with the demigod legion taking the child beyond the veil to be converted into a true deity. This process suppresses their memories as a human, in which they exist as a vague, half'forgotten dream. If the process does not happen, the spark will eventually become too powerful for the child to control, and will explode in a flash of destructive energy. The months in between the reveal of the spark and the child's departure to be converted is a lengthy process which the community takes part in. These social rituals and celebrations are meant to honor the child and their parents for their sacrifice, reinforce the symbiotic bond between mortals and gods, and to give the family the necessary time needed to prepare. During this time, the child begins to change, becoming faster, stronger, and more durable than mortals.
Their are problems with this scenario however. Due to the rarity of this honor, a growing boy or girl hitting puberty/adolescence can become snobby and self-righteous about their position (I was chosen by God because I am worthy, you are just lowly mortals, etc) and so on. Because of their physical and mental changes, they can become difficult to reason with or control. Alternatively, other families, out of jealousy or spotting a grievance with the family, may seek to harm or even kill the child out of spite.
The community needs a system in place that addresses these concerns. The true demigods do not interfere with mortal concerns due to celestial law, taking the child only after the necessary social rituals are complete. The child cannot simply be isolated in some far away place or hard to reach monastery, for their ascension is meant to be a long celebration that the community takes part in. However, they must also be protected and secured, for our sake as well as their own. How can these stipulations be met?