According to economists, the income of two siblings is more closely co-related than their height and weight. For example, if your brother is rich and tall, you are also likely to be rich and tall.
Take stocks. If you were born in 1970, the S&P 500 increased almost 10- fold, adjusted for inflation, during your teens and 20s. That’s an amazing return. If you were born in 1950, the market went nowhere in your teens and
your 20s adjusted for inflation. Two groups of people, separated by chance of their birth year, go through life with a completely different view on how the stock market works.
We tend to underestimate or overestimate the role of luck in our lives. If someone else does well, we say that the person is lucky; if we succeed unexpectedly, however, we tend to believe it's because of our hard work and strategic
timing.