Be prepared!! That's my best advice. Bring tons of 'safe' snacks or even bring a cooler of food with you as your carry on! Bring tons of whatever meds you need (OTC like Immodium or calcium, etc) and maybe, like Homebound, take a little more that usual before the flight. Bring relaxing music, anything to distract you before and during the flight. Do you know where your seats are on the plane in reference to the bathroom? Sometimes I like to be way in the back where I don't have to be too far from the bathrooms. And if you do end up with bad cramping in the morning, just tell them you'll have to stay behind then or whatever. I mean, if someone else in your family had an upset stomach one morning, I'm sure they'd work around it. Good luck!