I squandered my golden child! She appeared when I was busy, and disappeared before I could get back to the game and spend any time with her. I guess the golden child grows up to be a normal adult? And do I get another chance? I've solved 10 puzzles, have average 50 islanders and have been playing for quite a while. Must I start over?

The Golden Child never grows up - it's special! If your Golden Child is truly gone, there is no way to retrieve him or her unless you have a backup savegame file you can load from before the child was born. If you need help with how to do this, please let me know.