] I also found these words of his to Elinor interesting: "Mrs. Ferrars does not know what she may be doing -- what she may drive her son to." I suppose he was remembering his own sad history again there, but I wonder what he meant by that? If Mrs. Ferrars would drive her son away to elope, that could not be worse than what appears will happen anyhow.

Perhaps since Colonel Brandon does not know Edward very well he does know if Edward’s character is strong or weak. So, the Colonel may fear that Mrs. Ferrars’ immense pressure may drive Edward to disregard the obligation towards Lucy and the love Brandon assumes he has for her and abandon her in favor of a loveless marriage to a more socially and financially appropriate wife.