"My sister is only a baby. She can't defend herself if she's left in Georgia..." If Carl had a weak spot, it was definitely Judith. While it appeared as though he had a blatant disregard for the safety of himself and the rest of his group, Judith's safety was quite important to him. She was his sister. Yes, he'd lost his mother during her birth, but that didn't change the fact that she was just a baby. "I hope she's here."
The concept of multiple worlds was something that Carl was having a difficult time grasping. There couldn't be more than one world. But, then again, he'd believed there hadn't been such a thing as magical portals before his arrival in Storybrooke. And apparently those were real, so why couldn't multiple worlds be real as well? Maybe all the stories and movies he'd heard and seen before the outbreak had been real. Maybe they hadn't been mere stories.
"I had to," he said, his voice soft. "Shane would have killed my father. My mother would have become a walker. ...I didn't want either of these to happen. I didn't want to see my mother as a walker." Carl had very little remorse when it came to having to shoot Shane or his mother. It was just something that he'd had to do.
It wasn't that Carl was a cold child. Or savage and animalistic. But he was capable of doing things, doing things that would have made a normal person hesitate. A normal adult at that. But Carl's world wasn't normal, and neither was Carl.