/// <summary>
/// Determines whether the object has grandchildren.
/// </summary>
/// <param name="service"></param>
/// <param name="o"></param>
/// <returns></returns>
public static bool HasGrandchildren <T>(this IHierarchyService <T> service, T o)
{
ThrowIfInvalidArgs(service, o);
return(service.GetChildren(o).Any(c => !service.IsLeaf(c)));
}