Sins of Old Age: Is Ethics Age-Dependent?

On the way in this morning, the classical station played Rossini's "Sins of Old Age," a title that begs for consideration. There is surely a time before adulthood when one is not fully able to be a complete moral agent because of lack of knowledge, lack of maturity, and lack of experience. But generally, once one has reached a point of autonomy, we consider ethical duties to be ethical duties.

But are they? Are there acts that we do and should condemn in younger or middle-aged people that simply are not problematic once one reaches a certain age? Are there acts that we should expect from younger adults that elder folk should not engage in?
Professionally, for example, we expect senior people to be more involved in governance issues. There is a sense in which we have professional trajectories that seem to come with normative elements that change over time. Think of the Jimmy Buffett song "A Pirate Turns 40." There is something sad about a middle aged man acting like a 21 year old. At the same time, we sometimes see college students who are prematurely middle-aged, who are not taking full advantage of a time in life when they have the freedom to explore avenues and have life-shaping experiences that will not be open to them later on and it seems harmful to them, wrong in some sort of way.

Is ethics age-dependent in any interesting way? Are there sins that are particular to old age or indeed sins of youth?