[JabavuAdams]

Don't worry, you'll know when they're awake and distressed. I tend to let kids cry for at least a minute before intervening, well, unless they're old enough to be asking for help.

The alternative is madness and leads to divorce or murder-suicide.

EDIT> Actually, I just made that number up. It's all context. My main warning / peeve is that our unrealistic standards of care as modern, educated, intelligent, self-improvement-minded parents actually leads to a shitty child-rearing experience that produces somewhat shitty children, rather than a more laissez-faire approach. Crying is like the weather. We don't always have to fix it.

[pavel_lishin]

I agree with you, and hope I'll be strong enough as a parent to not always come running when my kid starts crying.

[DanBC]

When the child is under 6 months you probably don't want to delay when the child is crying. Under 6 months they cry to communicate a need - they're hungry; they need changing; they're in pain; they're cold' they're lonely.

Most people think it's a good idea to address those needs.

Even the people who like sleep training think you probably shouldn't start when the child is under 6 months.

There are a couple of people who think you can start sleep training under 6 months (Ferber; Gina Ford), but even Ferber sets a minimum age of 4 months.

If you are going to go down the "cry it out" route you will want to carefully investigate the different systems. Some of them have been discredited as harmful and cruel. Ferberization (or Gina Ford, they're pretty similar) is about the harshest system that a modern parent could get away with, but you need to be aware that a lot of people hate this method.