Seems like that's what eventually turned into the episode "The Child" of TNG. Which was earlier to be used in the never-made "Star Trek Phase 2" series a good decade earlier.

And even then, the episode only got made because there was a writers strike and they had to use scripts that were mostly finished already.

And even then the episode still sucked! It's currently ranked as the 170th episode out of a total of 176

It ended up manifested, sort of, in "Lights of Zetar" (or, you could make the argument, slumbered in the concept space all the way to Strange New Worlds' "All Who Wander").

"Lights of Zetar" - first episode I ever saw; don't think I was even a teenager. (Didn't always get to stay up that late.) Scared the heck out of me...

Not sure if it was really that great. Maybe because it was so dark outside that night? But yeah, wonderful memories.