Would they simply never grow? How would that exactly go? How much force does a growing human body exert on the box?
This is assuming you take care of their food, water and stuff obviously.
This is not hypothetical. Bits of human beings have been ritually imprisoned for ages and they basically deform to take the shape of the prison.
https://en.wikipedia.org/wiki/Foot_binding
https://en.wikipedia.org/wiki/Artificial_cranial_deformationhttps://en.wikipedia.org/wiki/Genie_(feral_child)
They become a documentary
Jigsaw, is that you?
Are we also giving them human interaction like hugs and communication? Because lacking that, a baby will also die.
Hmm, I don’t think they would die without hugs or communication. Nothing in the link exactly says they would die too, aside from some questionable sources from hundreds of years ago.
A human body would be able to biologically survive without hugs and communication (or even higher brain function honestly if you manage it properly).