It was very tough for Frank Jr. to try to live up to his father image and the kid wore his feelings on his sleeve. It was very obvious that he felt inferior to his old man at times; that is a terrible feeling to have. I think the old man was somewhat disappointed that his son was somewhat of a gentle person.

http://www.cnn.com/2016/03/16/entertainment/frank-sinatra-jr-dies/index.html
Life in general is tough enough but having a father like Sinatra had to have as many minuses as it did pluses.
Jr. had many doors opened to him that would not have opened if he was Frank’s kid and he knew it. That has to weigh very heavily on a person confidence and self-esteem. Everyone wants to become their own person and be respected as such. On the flip side, Jr. lived a pretty privileged life.
Personally, I didn’t care too much for Frank Sr. I thought he was very arrogant and pushed he weight around too much.

I saw an interview with an Italian comedian (his name escapes me) on TV a long time ago. The interviewer asked him to compare Sinatra and Dean Martin. The guy said; if I have a party at my house and invited them both; all night someone has to attend to Sinatra needs, he requires a lot of attention. On the other hand, we never even knew that Dino was there. My observation exactly.
Jr. died yesterday at the age of 72 while he was on tour.
RIP Frank
