Any other parents have an easy first child but a difficult second one?

I mean in forms of temperment, health etc. My daughter was soooooo easy. She slept through the night right away, was never sick, talked early and pretty much gave us no trouble. Then my son came along he had colic and need to be held almost 24 hours a day. He had delays and needed occupational and physical therapy. He was in the hospital twice before turning two. I tell my wife if our daughter was anything like our son she would be an only child. I think that is a big reason we my does not want three anymore. I always wanted to but I know she was hoping to sway me to three. Shortly after he arrived she said two was fine with her. Anyone else have kids night and day in terms of health, temperament whatever.