A few months ago DH's cousin picked up our half of a pizza tab. The total for all of use was $20 maybe, so our half was about $10. We ate 5 pieces of pizza total (my family) and they ate theirs and kept the rest. We offered money but she said to just pay them back with food when they come into town.

This Saturday his cousin and husband are coming into town and suggested we go to a certain restaurant down the road from our house. So my question is, since it's "our turn" to pick up the meal tab, do we owe them whatever their total tab is or just put $10-$15 towards it since that was about what they paid for us? I don't want to make it awkward or have anyone assume anything but their meals/drinks could easily hit $40-$50, plus we would have our own.

Thoughts? I want to be fair but don't want to come off cheap either....help!