def draw_children
      first = true
      @children.each do |child|
        child.draw(1, first)
        first = false
      end
      puts '└──'
    end
def draw_children
      first = true
      @children.each do |child|
        child.draw(1, first)
        first = false
      end
      puts '└──'
    end
Draw all children at the same level, for having multiple top-level
 peer leaves.