Before our children go to school we want them to be able to go to the toilet on their own. So is just prior to school the latest you can be toilet training your child? Most parents would want to be done with nappies well before that age, but not all children respond well to using the toilet. Monica Ferrie is a toilet training expert with Babyology's Parent School. She talks about what the research says in terms of the best age to start toilet training, and what to do if you have a late starter.