My 17.5 month old son has always been a terrible sleeper, but he's been able to put himself to sleep since he was about 12 months old. He began sleeping through the night at 15 months but recently, he's been screaming his little heart out at bedtime. I am using the same routine, I've tried medicating with Tylenol just in case it's teething pain and overall nothing significant has changed. So it appears we are going through the dreaded 18 month sleep regression. So, did you CIO, did you get through it by any way possible (ie: rocking, walking, bouncing....)? I don't want to create bad habits and lose my independent sleeper, but if it's just a phase and is short lived, I don't want to put un needed stress on me and my little guy.