(HealthDay News) -- Toilet training should begin only when the child is able to recognize and communicate when a diaper is soiled.

According to the American Academy of Family Physicians, this most often occurs between 18 and 24 months of age. But some children may remain in diapers as late as 2 1/2 to 3 years old, the academy says.

Before training begins, introduce your child to her potty chair by keeping it in her play area, the physician's group advises. Let her sit in the chair any time she wants to -- fully clothed -- but never force her to sit in it.

Finally, encourage her to sit on her potty chair without a diaper on. Show her how you place waste from her diaper into the potty chair, then transfer to the toilet. Allow her to flush the toilet and watch the waste disappear.