Rachel realized that her sister was normal. She still looked and acted like a normal 5-year-old. Rachel knew that she'd only been wishing for changes to affect 18-year-olds, but she'd expected more to change to suit it. She walked over to her mom's computer, opened the browser, and searched "18 year old." The first result was "Second Infancy." She looked at the article.
"Starting at age 16, developing brains will begin to regress. While still having many higher functions, the teenagers are rendered less independent and more infantile, often regaining infantile attractions, losing bladder and bowel control, and regaining the suckling reflex. This reaches its height at age 18, and declines until age 20, when the child is again weaned off of suckling reflexes and toilet trained."