How can I limit a hierarchical query to the point where there are multiple children?
Simplified with window functions:

with hier as
    (select   level as the_level, &lt;columns&gt;
      from &lt;tables&gt;
        start with &lt;predicate&gt;
        connect by prior &lt;child&gt; = &lt;parent&gt;
    ), levels as
    (select hier.*, count(*) over (order by the_level) as count_items
      from hier
    )
  select levels.*
    from levels
    where the_level = count_items ;