Try and steal any holy relic from any of the major/minor religions in faerun and you would be slaughtered on the spot, child or not( especially a tiefling). Even a Lawful Good diety like Tyr would have you tried and executed for such a crime.
I strongly disagree. This statement flies in the face of everything I've read about the Forgotten Realms, its good deities, and the good alignments in general.