When should we start toilet training? What are the "readiness signs"?

Base the decision to start not on age but on "readiness signs": (1) can stay dry for about two hours, (2) signals — by gesture or word — that they've gone (or are about to), (3) shows interest in the toilet or in imitating adults, (4) can respond to simple instructions, and (5) can sit stably on the toilet seat. When these come together, it's time to start. For children developing at a slower pace, the signs come together later too — and that's perfectly normal. Starting before the signs are in place tends to drag on and wear out both parent and child. Once you start, the golden rule is not to scold accidents and to celebrate successes wholeheartedly.