Sorry I can’t provide a cite, but here’s the story as I know it.
Saturday in Madison there was a fundraising event in which people jump into the local lake through a hole cut into the ice. A quick dip, and then they climb or are hauled out. There’s a pretty well known group called the Polar Bears club that does the same thing, but AFAIK that group was not affiliated with this event. It was very cold, single digits with a 20mph or so wind.
One of those who jumped was a 4 year old child. There was no apparent coercion by the parents. Nevertheless, I was really pretty shocked that it was allowed.
But I’m not a parent, so I’m particularly interested in parents reactions to this.