I'm traveling towards the end of the year and my fluffy Corgi will be almost a year old when we take the trip. At 14 weeks, he's weighing 15 lbs -- big ol' fluff ball. His breeder said she'd flown with one of her dogs in a soft-sided Sherpa bag, under the seat, and he did GREAT... I'm going to ask her about the size of the bag she used -- but I'm curious -- have any of you flown and what type of bag did you use? I certainly don't want him in Cargo -- I want him with me, under the seat (it's not that long of a flight) but I'm concerned about him fitting!