That's interesting because I looked at the title and assumed almost the direct opposite to you. I assumed that I would read the article and find something uplifting and happy about babies in Finland. And something interesting about cardboard boxes in Nordic climates.
I visited Iceland years ago and observed that babies were often left outside in prams (rugged up and only during the day) and it turns out that the locals believe that it's quite healthy to do so.
Reading about this more recently shows that this isn't unique and a lot of cultures in colder climates do this.