In many family businesses the succession from the founding father to the second generation causes new challenges. When parents and children are working together, the power lies with the older generation. From the moment that older generation leaves the organisation, the power has to be divided to the second generation. Siblings become partners and have to take care of the continuity of the organisation. The feeling of gaining power and leadership can cause friction between siblings. 

There are a few things which can help this succession succeed:

- Create family governance rules such as policies for family behaviors and a clear and shared vision for the future. It is important to respect and hold each other responsible to these commitments. 

- Create specific sibling-focused strategies. This can be a clear boundary between personal and work relationships. It�s also important that siblings recognize their strengths and weaknesses. Once they know who is good at what, they can decide how to divide the partnership. 

- Communication is very important. It�s wrong to think that your sibling knows what you are thinking. You make assumptions and create expectations based on what you think your sibling would do. This is a dangerous process. It�s important to talk openly about thoughts and feelings just as you would do with an non-family member in the organization.

Example of a successful sibling partnership: the Disneys

Source: https://theturnaroundauthority.com/2015/03/17/famous-sibling-partnerships-that-worked/ 

We all know who Walt Disney is. Less famous is his older brother Roy, who was his co-founder of Walt Disney Productions. Walt was the visionary; Roy was the finance guy, generally a less flashy role.

�Walt had this idea [for Walt Disney World]. My job all along was to help Walt do the things he wanted to do. He did the dreaming. I did the building,� he once told reporters.

They started working together at a young age, delivering newspapers after their dad bought a route. Roy was a banker in Los Angeles when Walt moved there and they founded Disney Brothers Studio in 1923 to produce short live action, animated films. In 2014, the company reported revenue of more than $48 billion.

Despite any lingering childhood issues, siblings can form successful partnerships.