I spent about 45 minutes atop my Musto Skiff watching the Golden Gate Bridge and the open ocean drawing ever nearer during a three knot ebb ! I'm in really good shape , but underestimated the effect that exposure to really cold water would have on me (read - total exhaustion)...
Kids have a greater surface area to volume ratio - so they tolerate extremes of temperature even less well than skinny adults. Make sure you have wetsuits of appropriate thickness for the conditions, without 'em you can be in trouble without even capsizing...
Also , don't assume power craft see you just because your mast is 30' high and you own a neon orange gennaker. I nearly got plowed under by a power boat that didn't see me until almost too late ... !
