Voice Vibration Effect - "Purr"

Hi all!
I’ve had a hard time trying to find information about this and hope I can get some pointers here. Kinda desperate :-s

I have a cute cartoony voice file that says “yay” and I want to make it sound like an cute alien creature, similar to this: https://www.youtube.com/watch?v=XSxXGCUqra4

The result I want is to have a cute alien creature voice that sounds like a purr. I see plenty of resources for creepy monsters stuff but nothing for sweet and cute. Wonder if this would be achieved with a filter that makes the sound vibrate or if the sound has to be overlaid with a purr sound effect and auto tuned?

So many thanks in advance!

My specs:
Audacity 2.2.0
Mac OS 10.13.1, High Sierra

If you copy & paste this code into Audacity’s Nyquist prompt

(scale 0.6 (sim (mult *track* (fmosc 27.0 (hzosc 27)))))

Then apply Nyquist prompt like any other effect, it adds a purr-ish effect …

If you want it to be cute you may have to shift the pitch up by about 50% before applying the code.