His new source of trouble sprang from the not anticipated misfortune of Isabella Linton evincing a sudden and irresistible attraction towards the tolerated guest. She was at that time a charming young lady of eighteen; infantile in manners, though possessed of keen wit, keen feelings, and a keen temper, too, if irritated. Her brother, who loved her tenderly, was appalled at this fantastic preference. Leaving aside the degradation of an alliance with a nameless man, and the possible fact that his property, in default of heirs male, might pass into such a one’s power, he had sense to comprehend Heathcliff’s disposition: to know that, though his exterior was altered, his mind was unchangeable and unchanged. And he dreaded that mind: it revolted him: he shrank forebodingly from the idea of committing Isabella to its keeping. He would have recoiled still more had he been aware that her attachment rose unsolicited, and was bestowed where it awakened no reciprocation of sentiment; for the minute he discovered its existence he laid the blame on Heathcliff’s deliberate designing.