It involves NOT setting arbitrary dates for things such as:
stopping bottles/breastfeeding
being out of nappies
sucking thumbs/fingers
having a comfort blanket
and probably lots more things I can think of.
Because all this sort of judgemental "ooh, I hate seeing a child of x age doing y thing" stuff is bullshit and none of anyone else's business. All children develop and achieve things at different ages and it would be very nice if people realised that once in a while.
No?