Re: Star Trek Movie FAQ
I'll be damned. It was in the script.
Scene 18 is when Chekov sees the child looking at him through the porthole. And indeed, in Scene 213A, the child wanders into the transporter room and gets next to the Genesis device during the countdown.
"They quickly settled on the slender island at the head of the bay, which they called 'Mannahatta', after an old Indian word thought by some to mean 'island of hills', and by others 'place of general inebriation'."
ŚNew York: A Documentary Film