He took to Heathcliff strangely, believing all he said (for that matter, he said precious little, and generally the truth), and petting him up far above Cathy, who was too mischievous and wayward for a favourite.
So, from the very beginning, he bred bad feeling in the house; and at Mrs.Earnshaw's death, which happened in less than two years after, the young master had learned to regard his father as an oppressor rather than a friend, and Heathcliff as a usurper of his parent's affections and his privileges; and he grew bitter with brooding over these injuries.

I sympathised a while; but when the children fell ill of the measles, and I had to tend them, and take on me the cares of a woman at once, I changed my idea.

Heathcliff was dangerously sick; and while he lay at the worst he would have me constantly by his pillow: I suppose he felt I did a good deal for him, and he hadn't wit to guess that I was compelled to do it.
However, I will say this, he was the quietest child that ever nurse watched over.

The difference between him and the others forced me to be less partial.

Cathy and her brother harassed me terribly: he was as uncomplaining as a lamb; though hardness, not gentleness, made him give little trouble.
He got through, and the doctor affirmed it was in a great measure owing to me, and praised me for my care.