Good advice friendowl. It comes down to consistancy. Young children need it. You can't expect them to go to bed at 8:30 one day just because you want them to if you let them stay up to 10:00 every other night.

The only parenting advice I can think of off the top of my head is along the same line. "No" should always mean no. Don't tell them "no" and then give in after some whining or crying. It will just teach them that whining or crying will get them what they want. Once you say "no" never give in. After a while they'll come to realize that whining and crying isn't going to help and they won't do it anymore. If it's something that is up for debate tell them "maybe" instead and then go from there. The trick is that, as the parent, you need to make the quick decision between whether something is "no" or "maybe".