inherit from ACTOR.
this is to add support for animal patients, HL7 v3 has that concept and we lack that in the RM to represent non human patients.
openEHR should be applied also to vet care and this is one small step towards that.
Agree in principal, and easy enough to do...
Yes, this would be just a new ACTOR subclass. No breaking changes here
Ref: FHIR "living subject" classification, ontologically this would be in the middle of the ACTOR and PERSON concepts of openEHR. https://www.hl7.org/fhir/v3/EntityClassLivingSubject/vs.html