[jerelunruh]

Singing does use a different part of the brain than speech and it would be interesting to know if it's similar to listening to whistling.

Someone in my family used to stutter badly but their singing has always been flawless

[Zancarius]

Not surprising. That was the same case with John Paul Larkin whose stage name Scatman John[1] probably rings a few bells. Although his style of singing lent itself well to (ab)use of stuttering. Very curious how that works, though.

[1] https://en.wikipedia.org/wiki/Scatman_John