$rs = $schema->resultset('Person')->search(
      undef,
      {
          alias => 'mother', # alias columns in accordance with "from"
          from => [
              { mother => 'person' },
              [
                  [
                      { child => 'person' },
                      [
                          { father => 'person' },
                          { 'father.person_id' => 'child.father_id' }
                      ]
                  ],
                  { 'mother.person_id' => 'child.mother_id' }
              ],
          ]
      },
  );

  # Equivalent SQL:
  # SELECT mother.* FROM person mother
  # JOIN (
  #   person child
  #   JOIN person father
  #   ON ( father.person_id = child.father_id )
  # )
  # ON ( mother.person_id = child.mother_id )