Re: Sailing with children
At those ages, I wouldn't plan to do more then 3-4 hours of sailing per day while they are awake and alert if you want them to enjoy it, and to have something fun to do daily, like going ashore and playing on the beach. How we have got in more is, Dad lift anchor and get going before they wake in the morning when the sun gets up nice and early. We can sometimes get in a few hours between them still sleeping, and just getting up for the day and having breakfast and not feel like we have been sailing 'forever'.
I think it is also good for the adult sailing to be tethered in this kind of a situation as well. Especially if the other adult is in theory sleeping as well with the kids.