Why does a charming, cooperative toddler suddenly become a stubborn, angry child, twisting, turning, opposing you in what you thought was a very simple matter, like putting on a sweater or getting into the stroller for a fun walk? Why do children have temper tantrums?

Although tantrums are part of normal development, they are very difficult for parents to deal with. In fact, temper tantrums can be set off by a variety of situations. There are many different causes, because a child deals with different frustrations at each age. Sometimes tantrums happen when a child begins to realize he is not the center of the world, and does not control everything. Your toddler is trying to be independent, but this is new and frightening to him. The 8-month-old may react with a tantrum when she becomes aware that you are not under her control. A one-year-old may tantrum when he realizes that he doesn't make everything happen exactly as he wants. A 15 month old child is ready to run about, climb and explore. She's ready to walk away from you but doesn't want you to be one to walk away.

Toddlers are exploring and delighting in their newfound freedom and autonomy. To be stopped suddenly and pulled away from some activity and worst of all, to be put on their backs to change diapers is often more than they can bear. Many fall apart and thrash around. Actually, it is too confusing for a child at this stage to be held down and changed.

At 16 months a child is able to understand what you say, but he's still not yet able to stop himself. He will understand, and even look at you every time he goes after a forbidden object. He'll look at you to wait for your reaction, but he doesn't have the ability to stop himself on his own. You'll have to help him with that for awhile. Learning to stop himself will take time.

It is particularly helpful for parents to be aware of the importance of sameness and routine, especially when dealing with very young babies and toddlers. Examples of common rituals are such things as a young child's bath time, or story time before going to bed. Your child may want a story read only in a certain order, or she may want only a special blanket, a favorite object, or a certain food to be given at a certain time. Even a simple change in routine can set off a tantrum.

Parents learn as they go along which routines and rituals are important to their child. Generally, if you can stay tuned into your child's routines he will become less and less demanding that things must be a certain way. Routines are your toddler's way of reassuring himself that his world is predictable -- that he has some control over what happens. He needs to believe this for a while longer.

It is also important to remember that young children have great changes in their moods and that this is normal and necessary. They can be excited and happy one minute, and intensely angry or afraid the next. Understanding this can help you keep cool.

It is not unusual at these times for parents to feel very angry with their child. Unfortunately, when parents act on these feelings by punishing their child, a vicious circle gets started. The child reacts to the punishment by becoming even angrier. The result is more and more tension between the two of you.

Once you recognize that your child's temper tantrums are normal, even necessary, it will be easier for you to respond because you won't feel that your child is attacking you personally. You won't feel like a failure. More important, you will be able to hang in there with him, instead of striking out or becoming frustrated and turning away. If you keep in mind that tantrums are a part of normal development, you yourself will be less confused and angry at those difficult moments. If you keep thinking that a tantrum is a natural overflow of feelings and not just a rebellion against you, you can stay calm.

Often, parents are advised to leave their upset toddler alone to cry it out rather than helping him calm down. However a child is not yet ready to handle these strong feelings alone. Toddlers need their parents as allies to help them express and master these new feelings. If mom and dad walk away, a child experiences his emotions as bad-- bad enough to drive his most treasured person away. The result is that he will hide his natural feelings and learn to disguise them. In addition the added frustration of being put in a room by themselves may cause more extreme behavior for some children. They may attack themselves by hitting their heads against the floor or wall, biting themselves, or holding their breath.

We have often heard parents use the term 'manipulate', to explain a baby's intentions. That word suggests that a small child can actually plan an attack on his parents, as if to say, "If I scream and carry on, I will get my way". We do not believe that this is the case. A baby gets out of control, and needs help to be pulled back together again. The routine approach that we will describe helps parents do just that.

If there is something you have decided is a definite "no", your child may tantrum. Let him. After all, he's probably really mad at you. You just sit down next to him, and say, "I know you're angry, and I'll stay here with you until you feel better. After your child has had a little time to express his feelings, he'll probably need help to calm down. Give him a little time to get over it, then pick him up and help him get into some other activity. The idea is to let him have this reaction and not try to distract him too soon.

If he starts kicking, hitting or banging his head on the floor, you have to stop him from hurting himself. Say, "I will not let you hurt yourself. I'm going to keep you safe." And then you can hold him for awhile. You may need to be very firm about this, but not harsh.

We find that this kind of response to a tantrum is a relief to both children and their parents. And furthermore, it works. Our approach can best be characterized by the word "empathy." Your empathy as parents is necessary when your child feels intensely uncomfortable, because everything in his world seems out of his control. With this approach, toddlers soon get the message that they can test a whole range of emotions and passions. Mom and dad are there to keep them safe, to set the limits, and to help them get back to feeling comfortable. In this way, you can actively help your small child.

Unfortunately, there is a tendency at these trying moments to see a child as bad, destructive, or manipulative. Our approach is different from the advice that is often given to parents to ignore their tantrumming child or their headbanging toddler by turning away or sending them to their room. We believe that leaving a child alone when he is upset doesn't allow him to express his natural feelings and creates an insecurity which will show up later on.

We have never heard a sensible explanation for expecting a toddler to be able to calm himself. When parents walk away or put a screaming toddler into his room by himself, she gets the message that strong feelings, and especially anger, are unacceptable. To leave a child alone with upset feelings or to react with threats of punishment or even spanking creates a feeling in a child of being a bad person. She learns that mom and dad don't want to be in her presence when she becomes upset. In response a child may begin to control his own natural feelings, but it will be a high price. A narrower range of feelings often develops because the child has gotten the message that strong emotions are bad somehow. That is not helpful in building an open, trusting relationship between parent and child.

It is very upsetting to a toddler to want something and yet be unable to get it. He doesn't understand why you won't let him have what he wants and what makes him feel good. And it's hard to explain it to him. Once he has language it will be a whole different thing between you, but he gets furious now because most of the time you do give him what he wants. So, when you suddenly say "no", he can't have something, it's confusing for him, and he doesn't yet understand why you're saying no. So, around the house try to let him do mainly what he wants, as long as he doesn't hurt himself. He's just not old enough to keep himself safe yet. We suggest you let him have whatever will not hurt him, or whatever is not important to you.

For toddlers, a house should be baby proofed, and for awhile, all breakables and valuable objects should be put away. In this way, parents have to say "no" less often. Your toddler needs to have plenty of things to touch and explore. This is the age when a child develops curiosity. At the same time a child needs to have firm and totally consistent limits set for him. As parents already know, a child cannot always be distracted from something he can't have. It is important for the child to hear a firm "no" from time to time, and for the parents to enforce that by physically stopping him--being firm but gentle. Parents should feel comfortable to say "no" at certain times and they should say it before they get angry. For example, when something is dangerous, the child must accept firm limits. There are other times, too, like when the child's actions are disrupting the family or likely to make parents angry. Rather than let the child continue to do something that is upsetting everyone around him, it is usually best to let him know he cannot continue.

Going through this period when your child wants to feel powerful and make all the decisions puts parents to a major test. Again, we remind you that this does not go on forever. After a few months of trying out "no," a child always learns the word "yes." Remember that it is extremely important to hang in there when your child goes through a tantrum. It's a way to build trust and openness in your relationship.

If you would like guidance on this or any other non-medical child development question, and you live in the Los Angeles area, you can call the Warm Line free of charge at 310-281-9770. A child development specialist will return your call within just a couple of days.