Not abolished per se but no longer issued to applicants after a certain date -I forget the date.
If passport with parent asnd kid issued prior to that date then ,within the normal validity period of that passport, it is still O.K. for child to travel with parent on one passport in and out of Ireland.
(Note I say "in and out of Ireland" -it doesnt mean that every country accepts the parent and kid passport, but i dont know of an EU state that won't accept it. If I'm wrong I'm going to get some angry parents !)