It was a complex situation in the comic. I recall it being someone associated with the antagonist groups, but the details are a bit fuzzy. Maybe you could look it up to get a more precise answer.
It's hard to give an exact age for Carl in the comic because his age progresses as the story unfolds. But generally, he starts as a young kid and grows up as the plot develops. Maybe around 10 to 15 years old at different stages.