Hello, We are in Week 2 of potty training out 21-mo son. He's doing great! My question involves naps and nights. Is it advisable to just put him down in thin cotton underwear from the beginning, in hopes of him "getting it"? Should I get rid of the diapers all together? With our first son, I put him down with underwear underneath a diaper; it seemed that this helped him learn not to soil during naps and nights within a month or so, before he was 2. On the other hand, I did not do this with our now 30-mo daughter, and her nap / night "learning" has been a slow and messy process with no signs of improving anytime soon. Thoughts?