Ok, When I said "always" in a PFD I wasn't really thinking about down in the cabin. The law around here (and I suppose most places) exempts children in the cabin from wearing PFDs and I have to assume there's a reason (I suppose if a child is in the cabin when the boat goes down, the PFD will do very little to protect them). I was envisioning the cockpit when I was saying that.
And yes, my child always wears a PFD on the docks. We have one similar to the ones that are pictured, although now that she's 30 lbs I need to find a new one.
I disagree that the main point of a PFD, especially for a small child, is to make body recovery easier. If a child falls overboard, whether that's off the deck of the boat or off a dock, a PFD will keep the child from sinking and make it easier to quickly retrieve the child out of the water. Hopefully within seconds. I have lived in (and swam in and boated in - though not sailed in) the pacific northwest my entire life and I am painfully aware of how quickly hypothermia sets in. A typical PFD will do nothing for that except hopefully make it easier for someone to pull you out of the water before it happens.
A car seat will not float with a baby strapped inside it. I am positive it will sink. I spend a lot of time with car seats because I'm a certified car seat tech, and although I admit I haven't thrown a lot of car seats in the water (hmm... maybe I've just found a new use for expired/crashed seats - mythbuster style!) I am quite familiar with their construction and I can't think of any except maybe one that *might* have a chance of not dragging your child into the depths immediately. The amount of foam in a car seat, if present at all, is NOT enough to keep it buoyant, I am sure. Even in a cockpit I am very concerned about something that will make a child sink even faster, and make the child even harder to pull back to the surface quickly, than the child would with no floatation device at all.
There has GOT to be some kind of solution for keeping an infant from bouncing around the cabin that doesn't involve using heavy-duty straps and buckles (which, by design are a bit difficult to unfasten) to strap the child to something heavy that will sink like a rock. And if there isn't, perhaps it's time to invent something and market it.
I am not advocating a child seat in replacement for a life preserver. I am advocating a secure place to keep the child. Good luck getting a child seat and a good life preserver on.
The principle damage, up above or down below, is them banging their head. They do not have adult balance. There is very, very little risk of a fixed keel boat capsizing in condition most of us would venture out in.
Our car seat did not sink. It floated long enough to get it out. Our child was not in it. I would hate for that to happen, as I stated earlier. But the odds of that happening versus them banging their head or being free to wander and falling overboard are significatly greater.
We used this dome contraption down below that was netted on top. I cannot remember the name of it but did a write up on here or other forums a while back. It was awesome if placed in the Vberth.
In bad weather, down below or up above, everyone has a jacket on. I also want to impress that not all life jackets are made equal. You really need a jacket that has a crotch strap and a head flotation. The mustangs seen above will flip the child to head up and out of the water. Many regular life preservers are not great at that, if they work at all. Believe me, safety on our boat is our number one concern.
The mustangs as described above have several differnt weght levels. I think it goes up to about 80lbs flotatoin. There is an infant, young child, and older child version if memory serves. We generally give our away to other families when they are outgrown (esp if they don't have what we feel is the proper jacket for kids).
This is a good discussion. Your concerns are valid. But what I am suggesting has worked for us and most long distance sailors. I would not suggest this for other smaller boats and certainly not anything with much of a tendancy to flip.
Thank you again for adding to the discussion.