Steven was Jack's grandson...
I have to admit, that Steven's death made me shed a tear... Jack and Steven had such a lovely relationship through series 3, and when Jack uses Steven to kill the 456, it made me sad. How could he use someone who he loved to fix something like that?
Also I must admit that Exit Wounds episode got me too, not so much with Owen's death... I figured he may die at the end of the series or at least play a lesser role as an "outcast" now that he dies forever. But the way they did Tosh's death got me too