I hate the AP tribe's inference that the only way to have healthy, happy children is to be attached to them 24/7 for their first 3 years or so.
It isn't 'natures' way at all! In nature, the mother's of small mammals have to go off to find food and leave their babies in between, crying or not. No young animal would develop the resilience to survive independently if their Mother was seeing to their every need and allowing them to develop such intense interdependence.
In third world countries, the babies may be breastfed and co-sleep, but their mothers are working in the fields all day to survive, the baby has to adapt to allow for life to go on!
I have two teenagers, one bf till 6 months, weanted to solids at 3 months and sleeping through the night by then, the other bf till 3 months, no solids until 8 months but sleeping through the night by 9 months. I was 'baby-led' by their needs, but I certainly had expectations and stuck to a routine of bedtimes that the babies understood.
My babies were put to bed warm and full of milk, we had a wind-up musical, fishy light thing in the cot when they were babies. It played for about 8 minutes and if they were still making noises after that, it was would be wound up again, and again until they were sleeping. If they (rarely) woke through the night, they were given a cuddle and put back to bed. Nothing else was on offer.
Somehow, despite me, they're both just fine. The best parents to learn from are happy parents with happy babies, not from militant groups who guilt you into believing that there are no other options - that's similar to the worst form of religious cults.