I think Parent/Childless works fine.

...lonely in the future.

Where did you find "childfilled"? Why do you think that it might mean "having children"?

Mommy/ Daddy ??

@MarcInManhattan I made "childfilled" up to demonstrate the sort of word I was looking for haha.

@Barmar that's a great point, I think the second point of contention I have is that the labeling isn't as satisfying as the top answer now "nonparent" vs "parent". A binary option is more clear that way

I've filled out plenty of forms, and I can't recall ever seeing this dichotomy. Usually they ask how many children you have, or "Do you have children? [] Yes [] No".

haha yes I agree in a form this wouldn't work. the full context is that I am designing a system for organizing parts in a supply chain, for a physical product. There are a ton of people involved who do not need to understand technical jargon, so I was looking for the best term to categorize Parts that have subcomponents, and Parts that do not. Right now a request we see is "can I see all of the basic parts", but "basic" is too subjective. That's why we were looking for something like "nonparent" or "childless" parts to accurately reflect what is being asked for

my thought was that by visualizing the system as a family tree, it would be easy for everybody to be aligned with the terminology. Therefore the concept of parent/children is important

The parent thing does not work for your purposes, I don't think.

component (basic part) / assembly (combination of parts)

@AO I would use some sort of simple/atomic vs composite distinction for your context, I think it captures exactly what you mean. (e.g. cl.cam.ac.uk/teaching/1314/DiscMath/DiscMathLecture02.pdf)

If a person is a parent whose child has died, which bucket do you want them in? Also - what about those who are parents but do not care for their children, such as absent fathers, or parents who have given their children up for adoption? IE are you looking for a word that means "currently has children" or one that means simply "has reproduced"?

@CongChen that is interesting! but i fear that atomic would not be understood by the laymen

@workerjoe in this context, we are looking to label a "node" or "person" at that specific time. so they either have children right now, or they don't

What’s wrong with parentless parts and parented parts?

In computer science you usually refer to nodes without children as “leaf” nodes, which I guess is mixing metaphors, but from experience students tend to get the idea.

@TinfoilHat parented/parentless is from the perspective of a child, but we were looking for a term to describe the adult... if that makes sense

@BenMurphy funnily enough we were using leaf before, but folks in other departments just couldn't grasp the concept

@AO If this isn't in relation to humans but rather in relation to parts in a supply chain, you should ask THAT instead. You'll be able to get much better answers that work better for your domain and don't eventually break down

Curiously, "with child" means pregnant so that doesn't work either.

@AO I would rather push for * childy (sim. to windy) to be introduced to the Englisg language :-D.

"folks in other departments just couldn't grasp the concept" looks like an ubiquitous language is required

Could you clarify whether you mean currently have or have ever had or have had during some specific period, and whether by "child" you mean "biological offspring", "dependent minor", or something else? Do you count deceased offspring? stillborns? estranged minors? estranged adults?

The question claims to be about people, but it's clear from the OP's comments that it's actually about categorising nodes. I suggest the question is reworded so it says what the OP actually wants, otherwise it could be closed as being in bad faith or attempting to subvert a policy (specifically the one on not asking for names for computery things).

Could you explain in more detail, please? What do your categories mean? A 'parent' may refer to either anyone who is or has been legally responsible for at least one child. Or it may refer only to anyone who is genetically parent of at least one child. Or it could refer to both. If genetic, some males may be parents but not know they are. Some legal 'parents' have adopted, so that there may be two sets of parents for the same child. All this needs to be clear before category names can be suggested.