Carl seemed to imply it with his monologue to Rick when he said, "They're all gone now" and "You couldn't protect them." And he puts Judith*, Hershel, and Lori, in the same sentence as Daryl, Glenn, Michonne and Maggie. It could be viewed either way, but I think Carl was concerned that everyone else was dead.
* Because he believes her to be dead. I think she's actually alive.