Haise was born because in the manga, Kaneki was Kishou Arima and got stabbed in the eye. This made him close to dying and lose his memories, including his name, but instead of death, Arima decided to keep him in a prison and think what to do with him.
Ken Kaneki has consumed Jason's kagune during their battle. He has said before that he hates eating humans so he kills and eats ghouls that are disrupting society. Even when he was Haise Sasaki he was never seen eating human food but he was the one cooking it.
He is not the original Kaneki. He is not Sasaki Haise. He is the Black Reaper a completely different person with the memories of both Sasaki and Kaneki.
The short answer : Yes. The long answer: He regained his memories from "Ken Kaneki" inside his own head. Therefore becoming Ken Kaneki again.
As experts would tell you, there is no age limit for dolls. It may seem unusual in this day and age, but several 12-year-olds still play with dolls. And in a world where the internet is widespread, this may be a good thing.
37 years (March 10, 1984)Chad Wild Clay/Age