Today's NY Times article, purported to be a piece that would hurt Fred Thompson's bid for the presidency, actually shows how principles Thompson is regarding issues and his ability to build partnerships that last. As to Thompson's sons being lobbyists, the article itself states:

"Senator Thompson was sensitive to the potential appearance of favoritism to his sons’ clients and sought to keep a distance. Rather than relying on his father, Tony Thompson relied mainly on political contacts in Tennessee he had made campaigning for his father, Mr. Mathews said."

Moreover, the Thompson boys did their lobbying almost exclusively in Tennessee, where Senator Thompson had no actual authority. Profiting off of perception is the American way - how else could Hillary Clinton be elected to represent NY or even be considered as a legit candidate for President (people think she has Bill Clinton's ear).