You can play as a baby in Mount & Blade II: Bannerlord. I have words, but I'm not sure why.
There's surely zero chance this is a bug. It works too well to be anything but a brilliant little Easter egg. All you need to do is press the R button while creating your character, and you can modify their appearance and background (thus, skills) as normal. But you're a baby now.
There are minor clipping issues on the in-game menu screens, inevitably, but it's surprisingly... well. I don't want to say "realistic", exactly, although I am currently checking with Graham whether the above is the accurate depiction of Scottish children I suspect it to be.
You can fight as normal, and in fact you're harder to hit and it might be coincidence, but none of the looters I skirmished with seemed to have the heart to attack me as long as my grown up employees were still around. I scored a kill. Damningly, the Bairnlord (of the family Waaaah) actually handles an axe better than my main character.
You even get a baby model on the map, and tiny clothes. Or as I started to prefer, you can be a carefree sprog running around in the nip with nothing but a fur cloak to indicate that yes, you are indeed the boss baby. Much of this likely comes from an official feature, unique to the sequel, in which the player character can age and die, but can also have children that you'll possess and play on with, much like Crusader Kings 2 or The Guild.
My favourite detail, though? When you talk to people, the camera often keeps your perspective, and they make eye contact.
I've struggled with Bannerlord's technical issues, and it may be a while before I can draw a firm conclusion on it. But my opinion is improving, and if nothing else, this has absolutely made my day. Good show, whoever put this in. Have a rusk on me.
Thanks to reader DavishBliff for the tip!