Complex sentence: Ash finds this situation intolerable; his soft-spoken cousin is apparently superior to him at sports, and everyone, including his father, Mr. Fox, is charmed by Kristofferson at Ash's expense.
Split into simpler sentences: Ash finds this situation intolerable where his soft-spoken cousin is apparently superior to him at sports. Everyone, including his father, Mr. Fox, is charmed by Kristofferson at Ash's expense.