We took two trips with one of our son's onboard (they were both between 6-9 months old when they went). Both did awesome and my parents enjoyed a week with their grandson to snuggle. Other than a good lifejacket for dingy trips ashore or sailing, they required nothing other than a good hat and some sunscreen. We didn't keep them in a life jacket "at all times" and they spent a lot time sleeping in a berth with their grandma as we sailed. We loved the experience!