This is a great problem to have! This is a huge decision, so we recommend that it is not hastily made.
When you have more than one capable successor, especially if they are family members, one of the best things to do is establish a well thought out curriculum for each candidate which clearly lays out the expectations and requirements necessary to someday lead the business. Once the curriculum is developed and effectively communicated, it is up to the successor to meet the performance expectations and training requirements of the curriculum.
Giving your successor candidates feedback on a consistent basis is important as it will provide coaching opportunities along their journey. After a period of time, have the potential successors, senior leaders, their peers and select direct reports assess each candidate’s strengths and weaknesses. What you are likely to find is that not everyone is willing to pay the price and make the sacrifice.
In the event there are multiple successors still in the running, develop an enhanced leadership development curriculum and let the cream rise to the top. If the strengths and weaknesses of the candidates compliment each other, an option may be that they share responsibility.
It is imperative that you do what is in the best interest of the company, even if it is not necessarily what might be the most popular decision among your family. Choosing one family member over the other or choosing a 50/50 Co-Ownership are both very delicate circumstances requiring deliberate action to ensure smooth sailing.  Remember, there is no business gain worth a family loss.
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