I posted the following idea on another site, but what if Cameron is "immortal", meaning she doesn't age?
I know she can get damaged from combat, but I doubt her synthetic flesh ever gets old and wrinkly.
What I'm implying is that maybe she has done all of this before: Gone to the past and helped John Connor grow up, I mean.
At a certain time, older-John sends her back to help his younger self grow-up into the leader he will become. Then, after he has grown up, he sends her back again, and then she helps him until he's old again, and then he sends her back again, and so on, and so on...
I mean, if she never ages, then she could just keep doing it over and over again forever. Sure she has to replace a part or two every once in a while(like in her arm), but it's not so hard when you're good at self-repair, right?
It's just a theory, but it would explain some things, like how Cameron knows where to go and what to do every night while the Connors are asleep; she already knows because she has done it all before. Each time she goes back she learns something new that will help her the next time.
This is fanfic. What's your opinion of it?