Maybe because of my age, (76) but when I first saw it most of the audience was my age. (mid thirties) Married with children around the age of 6 to 10. "Let's all sing like the birdies sing" was an old song even for us, but we probably would have heard it in the past. The entire audience sang along with it and swayed back and forth in there seats, held their children and it was a very moving show for us. There was a slightly scary part during the storm and the drums and the walls talking, but I never heard a child that seemed upset in all the times I went to it.
Push forward many years and I was sitting, solo, in the show and a fairly young lady in the space next to me had her two young children close to her side. But the "under new management" was the show and there was no "birdies sing" song, all there was was that screeching sound of Lago (Gilbert Gottfried). I looked over and the young mother was actually crying and I heard her say to her Partner(?) that she had waited all these years since she was a child to bring her own children to sing along with the birds. (an apparent significant memory for her as a child) and the song wasn't sung and there was a lot of screaming and upset instead of fun. That, my friends just about sums it up. One of the many declines caused by not reading the room and understanding that the concept is what sold the show not the age of the songs that were being sung. What is was happened to be pure nostalgia and corn, Yes, corny, it was something that kids loved and parents enjoyed as well. No pretense, just pure fun, with familiar easy to sing songs. Of course it had way to many years of the new management and missed a whole lot of kids that are parents themselves now but don't have the same motivation to bring their kids to it.