You might be traveling for long periods and waiting for long periods. Airport food can get old and get expensive in a hurry. Be prepared with enough for each person to have three snacks.
I highly recommend building in extra travel days coming and going when traveling with more than two people. That way, if you get stuck somewhere you have another day to get there.
Often standby passengers are the last to board which increases the chances of them checking your bag. Make sure your medicine stays with you.