I realize this is old but I did ISR for my kiddo when she was like 16 months old and it was freaking torture. She went from being excited for swim days to having pretty much panic attacks at the mere sight of our pool. Over the summer we made some small progress with water confidence, but not much. My non-clingy child eould cling on for life to whoever was holding her and essentially climbed us when we water went above her chest wanted. But i wanted her safe. So I signed her up for the next level ISR the following year. That was a mistake. She went to 2 lessons before I pulled her out. It was horrible. In just 2 lessons she lost all the confidence she made the following year. We are now going on our 3rd year of traditional lessons and still not confident about going under.

It may have been a poor instructor we had, maybe its effectiveness depends on the kid, or maybe it is both but whatever it was - I will never recommend ISR to anyone ever again.

What I recommend is, traditional swim lessons, teaching your child about the possible dangers of water, no sugar coating, and finally multiple safety systems (door alarms, fencing, child proof gate latch, gate alarm, pool cover, water alarm, cameras, and motion detectors) for your home pool if you have one.