Our boy Will was out on the boat at 11 days.



Until the baby can get itself into a sitting up position there's not a lot they're going to do on the boat. Other than require attention. For the first two months you have to be very careful about being out in the sun as they can't regulate their own temperature all that well. That and you generally don't want to be slathering anything on their skin. So you end up having to put the baby down in the cabin, and of course someone else generally has to be watching. This doesn't make for typical boating 'fun'. We used our 348 quite a lot less last year.
He'll be one this June and able to handle both sitting up and having sunscreen gooped all over him. So it'll probably be a lot more fun. He starts a baby emergency swimming class in a couple of weeks. Basically just how to hold his breath long enough to get up and floating on his back. Not that we expect anything, but between the boat and the pool it's good to be safe. That and the small lifejacket finally fits him well enough (none are really small enough for a baby under 3 months old). We're definitely looking forward to the adventure.
For anyone running a genset (built-in or redneck style) be absolutely sure you have a working carbon monoxide detecting system. CO poisoning is a cumulative risk and a baby is much more sensitive than an adult. Be sure to have at least one and make sure everyone on board knows what the CO alarm means and how to deal with it.