Why is the best interpretation that she was a prostitute of questionable age as opposed to just... a prostitute? Legitimate question, I haven't been following

Why is the best interpretation that she was a prostitute of questionable age as opposed to just... a prostitute? Legitimate question, I haven't been following this closely enough to know. If it was reasonable to assume she was an adult I don't see an issue with it, but I don't have a moral objection to prostitution