UK to Ireland. Pet Passport?

Yes you are supposed to have a pet passport but it's slightly bonkers. See here 

To sum up, it says because there is no incidence of rabies between Eire and the UK checks are "infrequent." If you go to NI you don't need one.

Thanks brue, we'll probably get one rather than risk doing without.  It'll be useful when we go to France anyway.

We have had one for our dog since the introduction of their requirement for Eire. We have made frequent visits and have never been asked for it or indeed our own but that doesn't mean we won't next time.