From his computer (which the Lone Wanderer can hack without Karma penalties), the Lone Wanderer can discover that young Arthur enjoys to write stories, has a crush on Sarah Lyons (because she taught him to kill a man by stabbing him in the kidneys), and that there is a Guns and Bullets magazine underneath a bed in the den.
The Lone Wanderer has a chance to witness him snatch a whiskey bottle off of Elder Lyons desk, which can then be found in his inventory. He can often be seen drinking the whiskey, or sometimes even beer.
If the Lone Wanderer talks to him and asks, "Do they make you fight?" He will say that he accidentally shot Sarah Lyons and says, "It was just a flesh wound", a reference to the fight between Arthur and the Black Knight from Monty Python and the Holy Grail.