You always wandered what it felt to be a helpless new born. But also wanted to see if you could do spells at a young state So you decide to make yourself so young you would be one. So you say "regress" and think 20 years younger.
You are then engulfed in a puff of smoke. Next thing you know it. You are lying naked in a pile of your clothes. Bald with no teeth. Look like you were born a short while ago.
You try to talk but all that comes out of your mouth are coos and gurgling sounds all while you kick your legs around. The book looks huge as you glance at it.
You wonder if being this young would mean you cant talk and do spells. But Im sure there was a safeguard. If you had book of beast and you assumed became an animal. You'd be able to turn back.
You decide you had enough fun and...