Carol will only have been gone for like 5 minutes by the beginning of tonight's episode. What, is she just going to come right back?
Carol grabs Megan, it makes sense.
I haven't been actually watching this season, so I didn't know that.
There is always the cliche in movies and tv about someone riding in to save the day that you thought was gone, and who couldn't logically know that someone was in trouble or where to go to save the day, but they do it because the script calls for it.
In this case it makes it even better that Corol just left, because then she just walked off camera, which makes it easy to walk back on camera and save the day.
"Take that Governor!" - Carol
"Hey everybody, Carol saved us! Where were you?" - Daryl
"Just standing out of view over there behind the camera. I was about to get a sandwich from the food truck, but I saw the Governor come and so I jumped back in and shot him." - Carol