"…With the capabilities of the Jesda family, I do believe that you did not believe the fact that, we actually did not find her after she left home." Benjamin explained.
Jack knew that what Benjamin said was true. After all, he had always been questioning himself that, if it was true that the Jesda family really possessed the incredible capabilities since long ago, then, how was it possible that, with Anne staying at Crystal City, it was difficult for them to trace her?
Just from the fact that, Nathan was able to know where Anne was, and had even orchestrated for her murder, Jack could tell that, it was true that, the Jesda family had the capabilities of knowing about Anne's whereabouts.