being the seventh son would mean that Tom would have little or no inheritance, but in many cultures being the seventh son gave you somewhat mystical powers to compensate for being poor. here the 7th son has the power to know everything, and thus knows that his wife is whoring herself out when he is gone, and ends up killing her for it. so in a way, a misfortune gives way to a blessing which gives way to a curse.
being the seventh son would mean that Tom would have little or no inheritance, but in many cultures being the seventh son gave you somewhat mystical powers to compensate for being poor. here the 7th son has the power to know everything, and thus knows that his wife is whoring herself out when he is gone, and ends up killing her for it. so in a way, a misfortune gives way to a blessing which gives way to a curse.