Today’s toddlers tend to complete potty training much later than prior generations. Twenty-five years ago, 90 percent of toddlers were trained by age two and a half. Now, one-third of children are still in diapers after their third birthday. Parents who wish to pursue a more lenient approach should prepare themselves for later completion of toilet training (or “toilet learning”), as well as questions and an occasional raised eyebrow from older friends and relatives.