Well 3peas when we first went crusing with our son he was 6 months old and it was quite an event. We secured his car seat to binncal with some rope the old fashion way. We built a lee cloth to keep him foward in the v berth when he slept. We would arange pillows around him to keep him in the centre of the berth. As for the car seat it was a god send when traveling by cab we did have a minor incident with another car thank god every one was ok including Josh in his car seat. As for the baby pen it woud be easier just to sleep with your little in your berth at anchor. By the way keep it simple is the best method for every one on the boat. As for life jackets every one wears one under way, in the **** pit at anchor the boys are ok under supervision but never alone. Enjoy your holiday and keep in touch, Rember it goes fast just a blink and their 6 and 4 next they are in their teens ask cruising dad he will tell you lol.