These threads always go in the same direction. It's troll-baiting, really.
First somebody "innocently" suggests bringing an infant on a camping trip, then a dozen people offer support before one or two people start to think about what's going on here, and post more measured, cautionary responses (lest the next headlines read: "Online Forum Advised Father To Endanger Child"). Now we've reached the stage where people are appealing to the parenting of yore, and modern aboriginal peoples, who supposedly camped with their children all the time ("our ancestors did it 1000s of years ago so it's perfectly fine, guys!"). It's only a matter of time before somebody realizes that infant mortality rates were alarmingly high until only very recently in human history, and modern Inuit people have access to electricity, modern building insulation technology, and gas heating.
The real problem is that you're not really asking the right people. I don't know much about pediatric care, and I don't expect any faceless someone on an internet forum to speak authoritatively about it either. There are specialists who work with children for a living, and have studied the subject extensively to get where they are. If you want to know about dental care, you don't ask a food forum about it (Hey guys, so I just got a new dental implant, is it OK to drink Coke with it yet? Oh sure, yeah. I love Coke, been drinking it since I was a baby. I did it all the time. Silly modern humans, Eskimos have been drinking Coke with dental implants for a hundred years now and look at them.).
And this is the Gear board on a backpacking website. Gear. What you want is a physician, some doctor who works with babies specifically. Ask them — that is, working under the assumption that what you want to know is what's best for the child. Not a gear board on a backpacking website. For now, I'm reporting this horrible excuse for a thread. Because it is not about gear in any way, shape or form.