The story
A four year old walked into his headquarters and called him Daddy.
Elena Hartwell ended things with Killian Thorne five years ago to keep her ruthless uncle Victor away from him, letting him believe she was a gold digger. He went back to his family's trillion dollar empire and she was framed by Victor and imprisoned, where she gave birth to Luna. Now Luna has tracked him down herself. A test confirms it, and Killian learns what the conviction really was and what Elena gave up, and starts using everything he has to get her out.