We tried with DD#1 at 18months, then again just after she turned 2 but she has only recently toilet trained and she turned 3 at the end of last year. It only took days this time which just made me think that for her, she was finally ready iykwim......where as previously, I simply felt like we were constantly I think I have become a believer of they really will click when they are ready, in their time but it doesn't hurt to keep trying every now and then to see if 'their time' has come