Sharing reports within the organisation but users with different domains

Hi,

Is it possible define users with different domains (daughtercompany.be and mothercompany.com) and who are not part of the same activer directory as "users from within the organisation"? We have sales reps with domains mothercompany.com who also do sales for the daughter company and thus should be able to acces dashboards and reports from daughtercompany.be.

Thanks!