If its viewed as a "first mistake" kind of thing that maybe they "fell in to" without realizing it might not lead to anything...key word being might.
if they have a history of not controlling their teenager - that is how this is viewd (the prom thing) as him not having his household in subjection, then this might get him removed.
That s one of the problems a lot of us have with the whole arrangement for servants in the Hall...so much of who is appointed and how they qualify is highly subjective and not at all Holy Spirit or scripturally based.