Discovery, Scientific
Half a century after the elves first opened portals to The Feywild, it was discovered that many elves were dying at incredibly young ages for their race. When they did, their skin and hair would loose all colouration and some bodies didn't remotely resemble the person who had died. Upon discussion with The Aspect of Sehanine, she explained these people were changelings, a race native to The Feywild, and that it was no surprise they were now also on the world, now completely intermingled with society.