Originally Posted by
etch5895
One word: Airbrau!
It is the very easy to find beer garden between the two terminals. As you exit the baggage claim / customs hall, walk outside of the terminal. You will be facing in the direction of terminal 1. Walk towards it, and the biergarden / restaurant will be to your right.
Good reco., but it will require the OP and his father to re-clear check-in/customs to make their connection to Ljubljana. Not sure how many "several hours" is.