diff --git a/.zuul.d/cross-jobs.yaml b/.zuul.d/cross-jobs.yaml
index ce6da7b886..b75f90a578 100644
--- a/.zuul.d/cross-jobs.yaml
+++ b/.zuul.d/cross-jobs.yaml
@@ -15,9 +15,6 @@
          Use the specified tox environments (``ALL`` selects all).
     vars:
       zuul_work_dir: "{{ (zuul.projects.values() | selectattr('required') | selectattr('name', 'match', '^(?!openstack/requirements)') | list)[0].src_dir }}"
-      # NOTE(jeblair): temporarily disabled tox_siblings until the fix
-      # in https://review.openstack.org/514058 lands.
-      tox_install_siblings: false
     files:
       - upper-constraints.txt
       - .zuul.d/cross-jobs.yaml