J.Z.
Hi R.,
You have already received some great advice from other moms! One of my biggest suggestions would be to try to plan the flight for your daughters naptime if she has predictable naps. My daughter ended up sleeping almost the whole way there and back! I also made sure to give her a bottle or sippy during take off and landing to subdue ear popping.
I have been to Vegas two times with my daughter to visit family. Once when she was 8 months old and last month when she was 19 months old. I'm not sure if you will be staying for longer than 3-4 days or if you will be renting a car. But if so...there is a fantastic store on Sahara about 20 minutes from the strip called Kid to Kid. It is a fantastic, very nice and clean, resale shop that carries everything you can imagine. You can purchase toys, strollers (although you should probably bring your own for the airport), clothes etc. Before you leave you can return them and they pay you on the spot. It came in very handy for us although we typically were there for 7+ days. My other advice would be to not overpack eventhough I am so guilty of it! You will be out and about most the time so just bring a few toys that your daughter enjoys. I also bought my daughter some things as we walked around. New stuff was exciting and held her attention! Bring enough food and snacks, diapers, wipes, formula (if needed) for two days and pack 1/2 of that in your carry on just in case. Remember you can always buy more there.
**Ask the hotel for an extra blanket so that you can put it on the floor for your daughter to play on in the room**
Most importantly, don't stress and have fun! Enjoy the weather and the wedding. You will be happy you made the decision to bring your daughter with and you'll get such pleasure out of watching her eyes light up at all the Vegas excitement!