There is an old saying to the effect that the sins of the father will be put upon the son. If that's true in this story, what sin (of Tom’s) has been put upon Penn and how does that affect his family?

Much of the novel is centered around what Tom has done — or is suspected of doing — in the past. There is an old saying to the effect that the sins of the father will be put upon the son. If that's true in this story, what sin (of Tom’s) has been put upon Penn and how does that affect his family?

Do I need to say possible spoiler alert? An extra-marital affair and one involving mixed races, producing a so-called "love child."

Yes to the above. Also, Penn is living with the question of whether his father knew what Frank was planning when he went to Dallas for that week and Tom wrote an excuse for him. I think he ultimately believes tha his father didn't know what was involved, but all through the book Penn's confidence and belief in his father is shaken.

Tom made a deal with the devil when he asked Marcello to protect Violet. That and his affair with Violet has really shaken Tom's faith of his father. Peggy, apparently, was aware of all of this prior to the chaos.

In his attempt to find the truth about his father's past, Penn has to separate truth from fiction in an unbiased way. This is a very difficult task for a son who loves and respects his father and his respective family, for what he discovers may be so contrary to the picture he has of his family and their relationships and past involvements. The truth may set one free, but sometimes the fallout is devastating.

We all like to believe our parents are perfect and Penn is no different. As he learns more about Tom and his disastrous decisions/mistakes and becomes more and aware that his father has feet of clay his view of the world is affected. To his credit Tom raised an honorable son who now struggles to maintain his professional objectivity even as his personal life is riven.

I think the biggest sin Tom passed to Penn is his involvement with the Double Eagles. The more Penn finds out about this time, the more he begins to lose his respect for his Father