Hi, J.!
This is a tough one alright! My boys are also a year apart and when they were younger I had the same problem. I was sooo tired of changing them both 2 or 3 times in the night. It got to a point that we kept a cooler at the side of the bed with 3 6 oz. bottles for each boy at night so we didn't have to keep making trips back and forth to the kitchen to keep grabbing them out of the fridge. My husband and I, on the advice of one of my closest friends was to have a bottle tossing ceremony. We prepped the boys for about a week, letting them know that next Tuesday was gonna be Big Boy Day and we were gonna throw a party so the big boys can throw all their bottles in the garbage. It was hysterical. We danced and sang and had baloons and the whole bit, complete with cupcakes. We put the garbage can in the middle of the kitchen and pranced around it like a bunch of fools and one by one the boys threw their bottles into the garbage. Yay! Hooray! No more bas, only big kids cups for big boys!!!
Don't get me wrong, they cried the first and second night. They whined for a few more, but they knew the bottles were gone and weren't coming back. I think by day 5 they were falling asleep without asking for a bottle. My daughter, the 4th child, is 2 years old and she was really really close to giving up her night bas but when I gave birth to baby #5 she decided to regress. My problem is that I'm not ready to deal with her fussing just yet. I'm currently nursing the little one at least 2x at night. It's only the 1 bottle when the 2 yr old goes to bed. I'm sure she will wean easily but sleep is a precious commodity for me right now and I'll allow her this battle in the meantime. LOL
For most children the next big step is never an easy one whether its potty training, bottle weaning or accepting a new brother or sister into their lives. Hopefully we can make it less traumatic for them, maybe even fun. As for your neighbors, if you are that concerned, perhaps as the transition is going on maybe you could drop them a thank you note or a basket of muffins for their patience? It's very considerate of you to think of them, but I'm sure they understand.
Best of luck!