Ms. A has two asset items. One is 1000 shares of Scotia Bank, another is 100 shares of a small business that she founded. When she drafted her will, she discussed it with her two sons. They all agreed to receive the same amounts when their mother passed away, and if the values of the two kinds of shares are different, one brother would pay half of the difference to another to make it even. At Ms. A's death, the shares of Scotia Bank are traded at $80 per share in the stock exchange market. However, the two brothers can only guess that their mother's company has a market value between $70,000 to $90,000, but they can not determine a specific value since they do not want to sell the company. As their tax advisor and executor, briefly explain the issues and provide high-level comments and suggestions.