15 moths old is a tough age. It's the age where they are now mobile and tend to not want to be held. However, I think a lot depends on the temperament of the child. My advice is happy kids will stay out longer. Alway have her wearing a flaotation device. Might want to have her wear the life vest around the house a bit before the season so she is used to it by summer. ALWAYS keep lots of snacks on hand: juice boxes, cherios, cheezits, whatever. Keep her warm and sunblocked, sunglasses, hat, etc. Have her help "drive" the boat and keep her involved as much as she is interested. In my mind, the sets still happened but they became more hectic and a bit more stressful. Take the time to tend to her needs and teach her between pulls because during pulls she will need to stay put. By the way, the advice on keeping them warm shaded and snacked has continued to work for way past baby/toddler age. Happy kids, happy sets.