Would be a good idea to share with her one of the existing threads that include things not to do in the UC during a long stay (sleep, leave her stuff unguarded, use a loud device without headphones, etc.). If there are plenty of seats left in the UC and you confirm that she can get back in the UC, it wouldn't be a bad idea to do a couple of power walks from one end of the terminal to the other for exercise and have a clear head for the (presumably) long upcoming international flight. Assuming you've advised her to be at the gate one hour ahead of departure, subtract that hour from the 9 hours.

4+ hours of Solitaire? Might be a good opportunity to try out some other games as well. My "downtime" folder includes Backgammon, Mille Bournes (1000 Miles), Gin Rummy, Hearts, Chess, and Rummikub.