when my middle son was 3 1/2, he had been day trained almost 6 months but was still waking up SOAKING wet every morning...like soaking through the diaper, through the jammies, washing the sheets every morning, soaking wet. one morning, dh had HAD it. he looked at ds and said, "son, i am done. there will be no more diapers. you will wear undies to bed tonight, and you will NOT pee in them." ds said "okay." and that was it. lol! he has been dry ever since. lol! i still can't believe it. now, with ds that is a little over 3...we are not so lucky. i've tried it all....i believe he'll be in diapers until he's 4. especially at night. all that to say...i don't know how to start working on overnight poty training. i COMPLETELY lucked out with the middle son, and i can't catch a break with this one. lol. good luck! it is TRULY truly a joyous day when you don't have to buy any more diapers. good luck!!!!!!!