In philosophy universality means that there are some general, unchangeable truths, it is an idea antagonistic to relativism which means that individuals and /or societies build their own truths according to their abitrary whim.
In the passage, it is clear that the parents want to force their will on their children, George asks his mother why everybody is pushing him, that means that he wants to make his own choices when he feels it is due time, on the other hand, Emily simply does not like George and tells her father she would rather be dead than marry someone she does not like. This shows that George and Emily want to make their own calls in their lives, they do not want to be alienated from their right to choose.
The Universal Declation of Human Rights in its first article says that humans are born free and equal in dignitry and rights, when parents, societies or governments try to coerse people to do their will, not the individual's will, this becomes an example of infriction on individuals' freedom.