But the vagaries of the grown-up kid are a consequence of permissiveness.
Of course, parents are not required to perform perfectly all the requests of the child. But every failure needs to be substantiated. The child will gradually understand that this does not mean neglect of his needs and love, and is only a consequence of necessity. To achieve results in matters of education, should be permanence. Not worth it in a few minutes to change my mind. It is particularly important to all adults in the family adhered to the same direction.
Even performing any reasonable request of the children do not need to drop everything on demand. Child should understand that you should take into account the interests of other people.
Uncontrollable and cranky child can be not only due to errors in the education, but for other reasons. Pathology of the nervous system, suffering a serious disease, adverse psychological climate in the family.
How can that be if suddenly the child threw a tantrum? The first thing to explain to him that talking to you and he will, once he calms down. If your serious tone is not effective simply get away so that you could not see, and will follow the child. Most likely you will be surprised how quickly he will calm down.
Patience, a necessary quality of any person. If the child gets everything he wanted, he got a passive attitude.