Coreyants Basically Northern Ireland is divided by religion
The Prodestants do want to stay in britain
The catholics do not (Generalisation)
The Prodestants are president atm so they will not let it happen
Plus Britain don't want to lose more and Ireland are divided but are busy trying to sort out Britain's mess
There has to be a vote in both Northern Ireland and The Republic of Ireland if that happens in accordance with the Good Friday agreement. Brexit kinda fucked up everything cause its gonna go back to borders and cause more division between the two countries if anything.