Insurgent-my thoughts and questions so far

                

                     While reading the squeal to Veronica Roth's bestseller novel Divergent, I've have had questions about the plot elements to Insurgent. First, I was wondering when Tris calls Tobias "Four", who does she talk to when she refers to Tobias as "Four." Sometimes in the book, she called him "Four" to Caleb and other times, she called Tobias as his real name to Caleb. Does she refer Tobias as "Four" when she's telling someone important information or it's kind of a second nature, I don't know.
                     My next question is if Tris really cares about her parents, then is she actually going to go look for the truth of what happened to them? I keep reading her thoughts about her thinking about her parents and wondering if anything happened to them when the Dauntless raided on the Abnegation at the end of book one (spoilers!)
                    A connection for the part I'm at in the book is a text to self connection. Tris is similar to me because she's outgoing, stubborn, witty, and ignorant.(She describes herself in the first book to be stubborn, but outgoing.) My actions relate to Tris' characteristics because in my personal narrative, I describe how I didn't want to go to that rock, I didn't want to wear that lifevest, but I did jump the rock.
                    I predict what'll happen next is that Tris, Caleb, Tobias, and Marcus escape Amity in search for the remaining Abnegation and Dauntless members. How it'll end is that there will be a huge fight and someone gets severally injured. They'll have to maybe (?) go to a different faction for a period of time and investigate the Erudite headquarters.
                  Edit (9/10/13): Reading a bit more of Insurgent, I got to know it a bit more. Some of my questions were answered and I gained new questions as well. One of the new questions is looking back towards the begginning of the book, would the safe house be better in a situation like this? The Erudite are seeking more important information so would it actually be best if everyone was hiding in one place? The book is getting better since the last time I read it and probably by next week, I'll have it mostly finished.