From a lot of experience, I can say that taking care of an orphaned newborn puppy is hard work. I have taken care of 12 orphaned dogs, of which 6 are still alive, and they sure gave me some happy and some sad moments.
When the mother dies, the poor puppies are alone, with no one to take care of them. I was one of those persons who begged his family to welcome them until they had certain age to take them somewhere else. That's where the difficult part begins.
The poor puppies are defenseless, so I never let one of them close to the big dogs because I was afraid they might kill him or something. Also, they need milk, and soft food. I always enjoyed watching them eating the whole stuff, since they ate like me when I am really hungry! I also bought them dog sweaters, for when the weather's cold, the poor things would die if it were really cold, and stuff for them to play with, like rubber bones and toys for them to chew on. I also played with them so they could be healthy and in shape all the time. It was fun running and them following me around!
The saddest part was when I had to leave them sleeping when I went to school. I always wondered, "Will it be okay without me?". I spaced out on my classes thinking that kind of stuff. I also was sad when they went to the veterinarian, I missed them so much, I was always worried sick. They were like my babies, after all.
The real pain was when it was sleep time. Every dog I had whined for unknown periods of time until they fell asleep, or I petted them a little so they would fall asleep. It was like taking care of a real baby.
All that hard work I was worthwhile, one of them is living with me, and the other 5 work with my father. Those 5 keep the place safe from robbers. I really enjoy paying them a visit. All of them are playful around me and my family, but they show no mercy toward strangers at night.