I thought of one other thing we're doing that will (hopefully) make the trip a bit easier. We live four hours away from London, where we were able to get our best tickets. We considered our options for getting down to Gatwick. When it was just the two of us, we always took National Express down rather than paying for all the parking, but the thought of a long, crowded bus ride in the middle of the night with two babies was just too much to bear.
In the end we chose to drive, but instead of using a car park by the airport, we are doing something different this time. We've booked a hotel/parking package for one of the airport hotels and will go down the day before our flight. Hopefully this way we'll have a good night's sleep, a nice meal, and we won't have to leave at two or three in the morning, drive four hours and then find the car park and how to get to the airport--all before even starting our 14 hours of flights and layover time. It will all be sorted the day before and we'll just take the shuttle, which only takes five minutes from the hotel to the airport, and the hotel is giving us a free cot, so we don't have to pack and unpack that.
The total price of our hotel for a family of four and parking for 2.5 weeks is only £40 more than just the parking at the airport at its prebooked price. It's about £150 less than the price for just showing up at the airport without pre-booking a spot online. Off-airport parking is a bit less, but not a whole lot more. I am still getting the hotel room for a lot less than a regular room rate for a family.
There were packages that cost even less than the one we chose because they use a local car park rather than the hotel car park, but I decided that I had more than enough to be getting on with that day, so paid a little extra for a hotel where I could use their own car park. Even doing that, I think I got a good deal. I just thought I'd pass it on since I hadn't heard of using hotels for parking at an airport until this year, and I think it will make the overall journey a bit easier and cut down on that worry about what might happen if something goes wrong during the journey down (such as road accidents, traffic, car troubles) because I'll be down there a night early.