Christian Is Not Jack's Father by JacobsDoubleWide

I think that Christian was chosen to mentor Jack, turn him into a healer and a leader, but he is not his father. Much like Eloise raised Daniel for a specific purpose, Jack was raised that way as well (he walked among his family, but was not one of them).

This is why Christian would drink and fathered another family. He wanted a real family, his own children. But knowing his place and having to be far away from his real kids caused him pain and he drank to deal with it. Once Jack was beyond his teaching he finished his duty and died in order to be taken to the Island to act as a guide yet again.

Since Christian is not Jack's father, who is? Well, I think it is Jacob. Jack will come to the statue as the timelines merge and be the one to lead Llana, Bram and crew against MIB/Locke. This could lead to a final scene with Jack killing Locke or even Locke approaching Jack on the beach saying how much he wants to kill him.