Quote Originally Posted by Irelandken View Post
Strictly speaking The south is a different country so yes she should need a visa, but if you're crossing from the north there's not actually a border control so no one will actually check, we do it all the time, just dont get arrested for something and need to be checked up on. As long as you're not comming into the country through a port or airport they never check.
NEVER play with immigration (especially for citizen from outside European Union), doing this is the best way to be in trouble. Being catch in a country requiring visa make you illegal stay. Ireland is in Schengen treaty and such incident is recoded in Schengen database and so may give trouble in all Schengen countries if you ask later a Schengen visa.

Being able to travel and not having a problem do not mean that others in different situation may not be in trouble...