def in_family(family)
      if self.class == Train::Platforms::Family && @name == family
        fail "Unable to add family #{@name} to itself: '#{@name}.in_family(#{family})'"
      end

      # add family to the family list
      family = Train::Platforms.family(family)
      family.children[self] = @condition

      @families[family] = @condition
      @condition = nil
      self
    end
def in_family(family)
      if self.class == Train::Platforms::Family && @name == family
        fail "Unable to add family #{@name} to itself: '#{@name}.in_family(#{family})'"
      end

      # add family to the family list
      family = Train::Platforms.family(family)
      family.children[self] = @condition

      @families[family] = @condition
      @condition = nil
      self
    end
Add a family connection. This will create a family
 if it does not exist and add a child relationship.