It does sound like something isn't right in your game. When you contacted support, did you provide the information that you have provided here? If you didn't, they may have thought that you were only asking how to find the doll and sent you here for game play help.

It will probably be necessary for you to contact support again, making sure that you let them know what generation your game is in, approximately how long ago you found the 11th toy collectible (with only the doll remaining undiscovered), and the latest event(s) you received that were related to the ghost girl. The events are probably where the problem is, so it's important to provide them with as much information as you can remember about them. Also let them know if you interrupted any of the children who were performing actions related to the event that you received.