Well I try very hard to look at the known and unknown unknowns... But then the metaphors might be pointing in a different direction.

(My personal pet theory is that The Girl is River, and she is the Master's secret daughter with Lucy that he sent back in time to keep safe. Hence the guy at the orphanage being all 'The child needs looking after!', like he was sort of brainwashed. And the Master, naturally, wouldn't be too worried about what that kind of upbringing would do to a child - if she went a little crazy, then all the better! *g*)