"There is no ideal age. You do it when the child is ready and that's more of a range. With girls it's two to two-and-a-half years, with boys two-and-a-half to three years. 'Training' is a misnomer. You can't train kids. They do what they're ready to do." — Charles I. Shubin, MD, FAAP. Baltimore, MD
"I usually start talking about it at 18 months, but it's not completed until the child is about to start preschool. I always let the child initiate the process." — Erin Thelander, MD, FAAP. Brooklyn, NY.
"When a child shows that they are interested — before age five." — Erik Cohen, MD, FAAP. Greenwich, CT.
To obtain these results, we randomly called 300 AAP-approved pediatricians in 50 states, then tallied the answers of the 20 who called back.