The recent decision in London Borough of Haringey v Ahmed and another  EWCA Civ 1861 (21 November 2017) is a good reminder of the need to take care when dealing with family representatives. The danger is that more vocal or sophisticated family members may not in the eyes of the Court command the legal authority of all of those whom they purport to speak for.
Best practice suggests ensuring that all family beneficiaries expressly give their consent to be represented by an appointed family spokesperson. Ideally a mechanism giving that authority (and ensuring those who give authority are properly informed) should be contained in the appropriate development agreement. Currently, authority is commonly given to surveyors but less so other parties. In future, perhaps developers and their advisors will pay closer attention to this issue.