Imagine if your business partner had died yesterday. What impact would that have on your business? Who would inherit their shares? That person would be your new business partner. Do you or they want that? Could you buy them out? Do you have an agreement on the value already? How would you pay for it?
This situation is very common and can be a disaster but with good advice your business and it’s shareholders can avoid this situation.
https://www.stuff.co.nz/business/103941354/businesses-shouldnt-get-stuck-with-a-widowed-shareholder