Does baby need to be put down?

[Snowy Sprout]

I noticed you can move the crib after hitting it with a hammer. I put it down near my garden so I'd hear it when the baby cried. When I picked it up again to move somewhere else, I saw the hunger/happiness bar filled completely again.
I was gonna just carry it until it was hungry, then put it down to feed it, but Baby never gets hungry if it's always in inventory.

Can I just carry the baby around in my inventory for three days to let it grow up happy all the time?

Does time I'm carrying it around not count towards the baby growing up?

[Snowy Sprout]

FWIW I carried my child's crib with me a lot, but I did put it down at night and a few times now and then. It grew up in about the same three days as usual. I'm not sure if it would have done so if I never put it down, but holding it did mean the baby almost never had to cry.

[kiraki]

The crib does not technically need to be down, they will age up regardless - we did this since there are some crib bugs and you may want to be able to move the crib