So I have pretty much anything and everything automated, from logs to milky porridge and bots, but I noticed at my housing section that some of the folk have sick faces, and I don't know how to fix it. I tried to give them water/milk, thinking drinks needed to be provided, but it didn't work. How do I fix it? - the happiness rating is going down bit by bit.

It's possible they're not actually in a Hut yet? Can you pick them up?

I found the problem; I had two robots serving both milk and water porridge, and they targeted the same folk, making them overfed. Hence the face. What I don't get is why when you overfeed them they stay sick, instead of reverting back.