My son is 20 months and we just started N75. He is in a toddler bed. I read chapter 7 of your book and am a bit confused as to if I put diapers (never pull ups) on him only during nap and bedtime or still keep him in underwear all the time and simply clean up the mess in the morning. The book seemed to say that the towel technique would only work for children around 30 months. Is that correct? Since night training is a natural process that takes time how do I proceed without confusing or frustrating him?