It is very common, they're trying to assert their independence and control, boundary testing. Constistency is the key, a child needs to understand for every action good or bad their are consequences both negative and positive. I have a picture chart of my sons 3 biggest offense, screaming tantrums, playing with water (ie flooding my bathroom) and purposefully peeing on my floor when he doesn't get his way. For each of those offense there is a consequence, screaming= time out to calm down, water= no computer time for that day, peeing on floor= no movie at bedtime. Because everything is represented with pictures my son fully understands the behavior chart and the other day after flooding the bathroom he came to me while I was cleaning and said he was sorry and got no computer that day I didn't have to punish him he did it himself. Have the consequence fit the offense, but make sure its meaningful to your child. Continued...
at 9:45 PM on Jul. 28, 2009