It is hard situation when someone from family or close relative undergoing any surgeries but having heart surgery is one of the most difficult for relatives. I am glad that your whole family especially the children managed to do everything around the preparation and surgery, that took a lot of worries from your mother's mind and I am sure she felt well having you all around. Hope that recovery will go straight forward and your father will be back to himself, of course it might take sometime and he should not over strain himself. But I think he is in good hands, wishing him to get well soon!