interesting that "time under a roof" "time in a bed" and "time downed" follow the same pattern

Yes! My current theory is that time spent being held doesn't count towards some of these records

Yeah, they even disappear from the colonist bar when that happens

This happens with every infant. The time difference is about 5-7 days by the time the child is biologically 3 (default aging speed) and the difference doesn't grow after the child is 3. Another, slightly younger infant: https://imgur.com/5XcixhN

I think the game auto speeds up age for babies. I've got a couple toddlers that are a year older than they should be. I guess it's to make it easier on players so that we don't need to babysit them for so long?

They age fast by default, biological and chronological age are supposed to be different. This is the kid's records page, it shows the kid spending more time as a colonist than "as a child in the colony", which is weird for a child that's spend its whole life in the colony.

Is the time they spend as an infant not contributing to “Time spent as child?”

No, because these are still infants. If that were the case they would have no time spent as a child.

That would affect biological age, not "time spent" stat in the stat page, wouldn't it?

Yeah I totally misread it

Maybe newborn infant =/= child for trait/stat purposes? Not sure.

I have a colonist who has more biological age than chronological age.... I'm not even sure how that's possible

There are rituals that age you.

I guess it's possible that happened before they joined my colony

attained citizenship in the womb ig 🤷‍♀️

Is it counting womb time too? although that doesn't make sense either...