Normal puppy development -NEMO

Saw this online so I know how nemo grow up...

The umbilical cord normally falls off within 2-3 days of birth. Infections of the umbilicus are rare in clean, well-managed kennels.
Puppies normally twitch and jerk while sleeping. This helps with the development of their nerves and muscles.

The puppies crawl well by 7-14 days, walk at 16 days, and have a normal gait at 21 days. They need to be on footing that offers traction. By 4 weeks of age, the puppies follow each other and carry toys in their mouths. They will play-fight with each other and learn how to inhibit their bites. If a puppy bites a littermate too hard, the littermate will yelp and stop playing with him. If the puppy is allowed to bite humans, he will not learn to inhibit his bite. It may be cute as a 7-week old, but it will not be as a 7-year old.

Puppies are born without teeth. The deciduous (baby) teeth start to erupt at 2-4 weeks of age. All of the deciduous teeth are usually present by 8 weeks of age.
The puppies' eyes will open around 12-15 days of age. The retina matures around 21 days of age. Puppies should see clearly by 4 weeks of age. Do not pry open the lids for any reason, as the immature eye is not yet ready to handle light. If the eyes appear swollen before they open, take the puppy to a veterinarian immediately as an eye infection may be present that needs to be treated to prevent loss of vision. Some puppies will take a day to open the eyes while others will take 3-4 days. The eyes will have a bluish color to them at first and then change to their adult color over time. If the eyes appear white or solid blue, take the puppy to the veterinarian right away.

The ears open at 14-17 days of age. They should hear clearly by 4 weeks of age. Deafness may not be noticeable while the puppies are together and first noticed when the puppy is in her new home.