As a species, changeling fairies are typically selfish and cowardly. Their natural reaction to danger is to fly away and avoid conflict. This is because despite their abilities they have no unnatural resistance to pain and illness, and in some cases are even weaker than humans. In their small form, changelings are especially vulnerable as they can be squished easily by the average person.
Since they posses the ability to switch genders as well as species (although not the ability to change race or coloring so they couldn't be a blue antelope for example) changelings usually pick the gender they most identify with at birth and stay like that for the rest of their lives. It is not uncommon for the gender confused to switch back and forth however. Also, fairies are able to tell if their babies are also born as changelings due to the fact that they are not born in the humanoid shape but rather as a random animal based on the child's genetic predisposition towards that species.
For more information, please PM Adam Siska.