Since there is no time in the Feywild, everything that exists in it has always been there, and everything that leaves it had never existed there at all. The histories of those still within it change such that events are altered so the erased person or thing was never there to influence them. Though this, of course, assumes the residents have any concept of things like "backstories" and "the past." It is more accurate to say that they never had them, until they leave, and upon being perceived by someone with a concept of linear time they suddenly gain a past that followed a sequence of events. This past is not random, however, and comparing multiple backstories seems to confirm that the events described did have a basis in reality. How these events happen in a timeless realm is, well, beyond the comprehension of primes like ourselves. It is perhaps better to say that these events all "already happened" and have never been in a state of "happening", as their occurrence takes no time at all.
Without time, residents do not have an age either. They are essentially eternal, and their outward appearance reflects moreso their mental age and maturity.
The Feywild is divided into kingdoms, each representing a specific part of the day/night cycle and always existing in that state. The kingdom of Aysa Shaeras, for example, is in a perpetual sunset.
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