The Ninth Amendment to the United States Constitution speaks rights, maintained by the people, that are not expressly mentioned in the Constitution. It is part of the Bill of Rights. There are other rights that may survive aside from the ones explicitly mentioned, and even though they are not listed, it does not mean they can be violated.
When two people speak the same language, they are able to understand one another better as well as express their feelings with less complications. The better understanding between the two people will allow them to form a better bond and therefore have a closer relationship.