Answer:
I think it's the relevant information that supports an argument or the opposing argument to the main viewpoint.
The biggest issue with this is that the first sentence is run-on, you should consider breaking it into smaller sentences, maybe by getting rid of the "and" after describing the mother, replacing it with a period and letting the father get a sentence of his own. Also, you could try "-on how happy the Railway family is. The story also uses detail on how nice the parents are-" something along those lines, just to break the run-on sentence?
This is minor, but at the end "creates a sense of perfection, by describing their house-" the comma before by isn't necessary, and can either be deleted, or you can rephrase like "a sense of perfection. The story does this by describing-"
I hope this helps! <span />
Answer: No, I don't think it's unrealistic or overly romantic because, you know, we get movies like Twilight and 50 Shades of Grey... so this one's a lot more realistic and, well, healthier.
Explanation: This is a true love story: a story of two very flawed humans learning to forsake their own wills, to facilitate the good of the other, because they first and foremost love goodness. Their love story is reasonable and yet transcends reason. It is made up of the deepest stuff of human existence: something deeper than feeling and thought; emotions and logic puzzles—it is made up of the will. Elizabeth lets virtue guide the choices she makes; and the result is not a happy ending, but a joyful beginning.
Hope this makes sense. :)