Whilst on this mission, he met Dr. Daniel Jackson, who he struck up a friendship with, and because of whom, didn't send the bomb through to Abydos.
Jack paid the price of his job, when his son Charlie shot himself by accident with one of Jack's guns. This has never left Jacks mind. After this, his wife, Sara left him.
Although almost always flippant and sarcastic, Jack enjoys his job, and annoying Daniel even more, by calling his artifact, rocks.
Even though he is sarcastic about Daniels work on the program, he protects him as much as possible, like a brother.
Jacks been through his share of nasties. He was almost implanted with a Gou'ld by Hathor, has been shot with arrows, watched his best friend 'ascend' and yet still carries on.
He has a unique friendship with all of his team, but mostly with Major Sam Carter. Their relationship is a very much 'are they aren't they' relationship that has the SGC and the fans guessing.
