My bf said He would ignore when the kid cry for attention and probably leave him in the room until he/she stop crying. What do you think? Ethical or not? Would this be a good discipline method instead of spanking?

I believe this is what is known as a temper tantrum.

If you are absolutely certain that the child does not actually need something, I believe it is best to ignore them. Certainly you do not want to teach them that their crying and whining (for no good reason) will get them what they want. That is how you raise a brat.

Depends on the age of the child too of course.

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When my toddler is out of control she often needs help calming down. I will let her throw a fit for a minute, and then I will remove her to a safe place, such as her bed, and let her cry it out a little longer. By that point she's forgotten what she's upset about and is ready to be comforted.

It is so tough to know what to do. If my toddler is being a brat I will ignore her because nothing else I do makes her happy anyway. As long as feelings aren't hurt (or her body) I just let her cry it out. When she's done she wants to cuddle and I am more than happy to do that because I just love her so much and want her to feel loved as much as possible.

If you are sure that it is a "fit" or tantrum, then yet, I always found it best to ignore negative behavior and reward good behavior.(The reward here being my attention.) From VERY early on, my son understood that tantrums were just not tolerated. I never hit him, or punished him too severely when he did something wrong, but one difference may have been that we just taught him from the begining AHEAD OF TIME what behavior was expected of him. We trained him in the way we wanted him to be and didn't only start when bad behavior started and would have then meant retraining him fromthe bad behavior. So, ,that's my 2cents worth!

I think that this can be a touchy subject when you have a new baby. Do you comfort them or do you let them cry? Some people say that a new baby needs to be held every time they cry because they need to feel secure. Others say that a new baby needs to be left alone when they cry because if you come to them you are training them to cry for attention. I personally think that you should comfort your baby when they cry. At this point in their life they don't know how to "train you." It's when they get older you need to crack down on the temper tantrums and comfort the other stuff.

I think you have to learn to recognize a tantrum and a true cry for help. Sometimes babies will cry and cry even if they've been fed, changed, and are lain down for a nap. As a parent it's your call. Personally I could never let my own son cry for too long unattended.