Because Ace is just the alter-ego of Nic, who is the alter-ego of Alex, and Jace is the alter-ego of Jason, who is Alex's little brother. Being alter-ego's, they're way too similar but way too different from each other at the same time. I don't know how else to explain it...
I'm never what I like I'm double sided And I just can't hide I kind of like it When I make you cry 'Cause I'm twisted up, twisted up Inside
When I use caps I do not want you to read it like a little screech, I want you to read it like a 5,000 year old ogre with the strength of 10,000 men. — avianwings47