Conflicts within families are common because everyone who is part of the family is also an individual, with their own viewpoints, beliefs, thoughts, ideologies, opinions etcetera. People with strong personalities do not give in or take to another's views easily because they not only think that they are in the right, but also believe that everyone else must do what they want without opposing them. It is not so much an opposition, but more a want to be heard and considered that causes conflicts. Barriers go up when one party does not want to listen to the other, just because they think they are right. It also boils down to wanting to control and a lack of freedom.
This is true of not just families but in every other walk of life. It is the 'I know best' attitude that ruins relationships. One must be willing to listen and also be capable of understanding. There is a way of putting one's point across, especially within a family. Decisions must be in consultation with family members and a mutual consent must be arrived at.
"A love affair with knowledge will never end in heartbreak" - Michael Garrett Marino