For youngsters who are physically and psychologically ready for toilet training, summer may be an ideal time to begin, according to a statement on the topic from the University of Michigan Health System.

The reason why is simple. As the temperature climbs, most children wear fewer layers of clothing, making it easier for them to undress themselves to use the potty.

Parents embarking on the process of toilet training -- in any season -- should remember that the "best way to accomplish it is with very tiny steps," Dr. Julie Lumeng, a developmental and behavioral pediatrician at the University of Michigan Health System in Ann Arbor stated.

Parents should realize that their child will not automatically progress as quickly as they might wish from unfamiliarity with a potty to using the toilet routinely, she explained. In fact, parents should consider it a "big accomplishment" just for their child to sit on the potty, she said.

Since every child is unique, there's no hard-and-fast answer to the "million dollar question" -- when is a child ready to begin toilet training? However, there are several signs that may indicate a child's readiness for toilet training, according to Lumeng.

One is that he or she is able to understand instructions. Children should also be able to support their weight as they crouch down to sit on the potty or stand up from sitting. They should be able to put their clothes on and take them off or pull them up and down, and their bodies must be developed enough so that their bladder can hold larger amounts of urine between trips to the potty.

Psychologically, children must be able to recognize when they need to use the toilet, be willing to sit on the toilet and should be uncomfortable in a wet diaper, Lumeng advised.

Another clue that a child is ready to begin potty training is if he or she is able to stay dry overnight, as well as the ability to communicate a need for a dry diaper, Lumeng added.

Generally, children are ready to learn to use the toilet between the ages of 18 months and 2.5 years, according to 1999 guidelines released by the American Academy of Pediatrics. Most children are trained by 3 years old.

Yet those ages are not set in stone. Parents of 3 year olds who are still struggling to train their children "shouldn't feel bad about it," Lumeng said, adding that there is "no medical reason that they have to be trained by then."

Toilet training typically lasts up to three months, but can take as long as seven months, and mistakes during that time are common.

The key to success, Lumeng said, is to "be consistent in positive reinforcement."

If the whole process gets too frustrating, however, parents should consider taking a month-long break before starting again. This is particularly true when the child begins to get more satisfaction in resisting his or her parent's wishes than in receiving compliments for his or her potty successes and other types of positive reinforcement, Lumeng said.