Casey (a new business client) approaches you for financial advice. Casey and her business partner, Josh, are joint directors and shareholders of the company that operates their business. Both of them have partners and children. They have both borrowed against the equity in their homes to provide the start-up capital for the business. Casey has a will that was made prior to starting the business and the birth of her children. Apart from setting up the company, she and Josh have not done any formal business succession planning. Explain to Casey the most important reason why she should have an estate plan for her business.