As their eyes begin to open and first steps are taken, puppies begin to explore their new world.
Puppies should now have begun to pass urine and feces without their mother's help. If this development doesn't happen by the end of this stage, a trip to the vet is advised.
During the weaning period, the mother still provides for all of the puppies' nutritional needs. The vast majority of food is taken through milk, however, some puppies may begin to eat solid food regurgitated by their mother. Most will now be able to lap water from a bowl.
First steps are taken and puppies begin to play fight with their siblings, and may even begin to practice growling and tail-wagging as social interaction begins.
Their eyes and ears are now working to some degree and puppies begin to react to light and sound.
A puppy's mental and physical development is aided by a complex environment. A responsible breeder will provide puppies with an increasing amount of human interaction, a range of toys, noise and other stimuli as this stage progresses.