Such as this: the relationship that you have with your brother or sister (the opposite sex of you) is a good predictor of your own marital success. Also, being an older sibling puts you at an advantage in marriage, especially when you marry someone who is also an older sibling. Why is that?
We didn't go over that question specifically, so here are my thoughts. Having brothers and sisters, in my opinion, is a great way to get to know the other sex. Otherwise, you could be pretty lost. Understanding the other gender has always been a great mystery to a lot of people, so having siblings is a good and easy way to break down those barriers. Also, it seems pretty clear to me why being an older sibling is so beneficial. Assuming that the role of being an older sibling has been executed correctly, the older sibling is much more capable in charity, love, problem solving, communication and responsibility than younger siblings - and this is all because of what is expected of them. Older siblings usually set the bar, the example, for the rest to follow (or not follow) and are usually expected to do a lot to help around the house. These are great skills to have in order to have a happy and successful marriage.
It's no question that parenting is hard, but just like communication is important in a marriage, it is also important, if not more so, in parenting. It is vital that the parent and child understand one another, that they are headed in the same direction together to build each other up constantly with new knowledge. In fact, if good communication is used everyday with everything, the child is more likely to be happy and well-behaved, in and outside of the home. Good communication helps the child to feel understood and respected, and this helps significantly with every aspect of the relationship.
So, if you want things to go smoother with your child, try honest communication. Don't yell. Listen - let your child speak their mind and heart and validate it. Consider their wants and needs. Speak on their level, not under or over it. Be reasonable and calm. It will work wonders.