Over on Adafruit, our pal John Edgar Park has a fantastic tutorial up on replacing the brains of a Fisher-Price See N Say toy with a CircuitPython-powered KB2040 microcontroller so that you can make it say whatever you want.
John made a "City Sez" toy that plays back urban sounds like a fire engine, police siren, dog barking, jack hammer, etc.
The awesome art for City Sez was done by Brian Kesinger. You can use the art and the sound files as-is or create your own.
Note: This hack will only work on modern, electronic versions of the See N Say, not the vintage, mechanical ones.