INVALID_FIELD  Cannot reference a foreign key field cms__Content_Layout__r.
=== cms__Content_Template_Relationship__cRef86 [1]
STATUSCODE     MESSAGE                                                       FIELDS
─────────────  ────────────────────────────────────────────────────────────  ──────
INVALID_FIELD  Cannot reference a foreign key field cms__Content_Layout__r.

Select c.cms__hasChildren__c

...

,(SELECT d.cms__Auto_Create__c
         ,...

         ,d.cms__Content_Layout__r.cms__isPageCacheable__c

         ...
         FROM cms__ContentTemplateRelationships__r d
         ORDER BY d.cms__Content_Layout__r.cms__Name__c ASC
)
FROM cms__Content_Type__c c
WHERE c.cms__Site_Name__c = 'IXPortal'
ORDER BY c.cms__Name__c ASC