Interesting thread, but I don't have much of an opinion. (Which is quite odd for me). I'm always fascinated by the passion this topic inspires.
I did practice CIO with both my children, not that I knew this terminology at the time. After they had been fed, burped, changed, swaddled firmly, kissed, tucked in so their dummy was "wedged" in, I shut the door and if they cried I wouldn't go back in. But, as a general rule, if they cried it wasn't for long.
However, I'm the first to admit that they are both pretty good sleepers. Whether that's innate or as a result of what I did, I'll never know.
My almost-3-year-old still sleeps from 7pm until 8.30am. She has a 2-hour nap in the afternoon. But I'm tipping she's not the norm.
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