I knew my DD was weaning herself at 13mths when she started comfort sucking only, no proper feeding. But I was pregnant with DS at the time and I don't think I was producing much, if any, milk for her. One day I tried to put her on but she wasn't interested at all, so that was the day I decided to stop. And she didn't miss it. She started to put herself to sleep too, instead of me feeding her. Just keep offering Kai but if he isn't really interested, he's probably ready to wean?