How we cite our quotes: Citations follow this format: (Book.Chapter.Paragraph)
Quote #7
The Easter party at Brideshead was a bitter time, culminating in a small but unforgettably painful incident. Sebastian got very drunk before dinner in his mother's house, and thus marked the beginning of a new epoch in his melancholy record of deterioration, the first step in the flight from his family which brought him to ruin. (1.5.214)
Charles reveals information about Sebastian’s alcoholism as he slowly becomes aware of its causes. He earlier said that Sebastian drank to escape – now he has clarified his point further: Sebastian drinks to escape his family.
Quote #8
"No," said Brideshead, "I don't suppose you could. I once saw my father drunk, in this room. I wasn't more than about ten at the time. You can't stop people if they want to get drunk. My mother couldn't stop my father, you know." (1.5.268)
We can interpret the common thread here as Lady Marchmain, not as genetic predisposition to alcoholism.
Quote #9
"It's no good, Charles," she said. "All you can mean is that you have not as much influence or knowledge of him as I thought. It is no good either of us trying to believe him. I've known drunkards before. One of the most terrible things about them is their deceit. Love of truth is the first thing that goes." (1.5.375)
Lady Marchmain doesn’t seem to have much knowledge of Sebastian herself. He was always much more interested in beauty and happiness than he was in truth.