I had a bridal party of that size, 10 kids under the age of 7 as well. Was a challenge but as long as you know it going in you can prepare ya know? Good luck!
I had 18 last weekend, which is hard enough. Whew!
just get your few big bridal party shots out of the way ASAP. With that many people, it is so hard to keep everyone's attention, especially if they have been drinking.
Biggest party to date has been 24. Come prepared, and try to get some help from the locals as it may be like herding cats. Lots of possibilities, though!