However, this is not always the case for children with developmental delays or disabilities, such as autism, Down syndrome, mental retardation, cerebral palsy, etc. Children with special needs can be more difficult to potty train.
Most children show signs of physical readiness to begin using the toilet as toddlers, usually between 18 months and 3 years of age, but not all children have the intellectual and/or psychological readiness to be potty trained at this age. It is more important to keep your child's developmental level, and not his chronological age in mind when you are considering starting potty training.
Signs of intellectual and psychological readiness includes being able to follow simple instructions and being cooperative, being uncomfortable with dirty diapers and wanting them to be changed, recognizing when he has a full bladder or needs to have a bowel movement, being able to tell you when he needs to urinate or have a bowel movement, asking to use the potty chair, or asking to wear regular underwear.
Signs of physical readiness can include your being able to tell when your child is about to urinate or have a bowel movement by his facial expressions, posture or by what he says, staying dry for at least 2 hours at a time, and having regular bowel movements. It is also helpful if he can at least partially dress and undress himself.
Children with physical disabilities may also have problems with potty training that often involve learning to get on the potty, and getting undressed. A special potty chair and other adaptations may need to be made for these children.
Things to avoid when toilet training your child, and help prevent resistance, are beginning during a stressful time or period of change in the family (moving, new baby, etc.), pushing your child too fast, and punishing mistakes. Instead, you should treat accidents and mistakes lightly. Be sure to go at your child's pace and show strong encouragement and praise when he is successful.
Since an important sign of readiness and a motivator to begin potty training involves being uncomfortable in a dirty diaper, if your child isn't bothered by a soiled or wet diaper, then you may need to change him into regular underware or training pants during daytime training. Other children can continue to wear a diaper or pullups if they are bothered, and you know when they are dirty.