Characters take on life sometimes by luck, but I suspect it is when you can write more entirely out of yourself, inside the skin, heart, mind, and soul of a person who is not yourself, that a character becomes in his own right another human being on the page.
Eudora WeltyEver since I was first read to, then started reading to myself, there has never been a line read that I didn't hear. As my eyes followed the sentence, a voice was saying it silently to me. It isn't my mother's voice, or the voice of any person I can identify, certainly not my own. It is human, but inward, and it is inwardly that I listen to it. It is to me the voice of the story or the poem itself.
Eudora WeltyWhat I do in the writing of any character is to try to enter into the mind, heart and skin of a human being who is not myself. It is the act of a writer's imagination that I set the most high.
Eudora Welty