north korea may be about to take the first steps to the change of leadership. but what if it remains a family affair. brian todd is looking into it. >> it's the biggest political gathering in north corina in decades, the so-called worker's party congress wherell kim jongl will announce changes at the top. that may well mean he'll lay the groundwork for his third son to take his place, a transition that has many in western intelligce worried about what comes next. i spoke about him with dick shaw, who dealt with the regime as a member of president bush's national securityhi council. >> the third son in his 20s is the designated successor, but clearly doesot have the -- have the party credentials