I don't think this is anything to worry about, its quite normal. The puppy will only be dreaming :-)

Any of various mammals of the order Marsupialia, whose young are very undeveloped when born and continue developing outside their mother's body attached to one of her nipples. Most marsupials have longer hindlegs than forelimbs, and the females usually have pouches in which they carry their young. Kangaroos, opossums, and koalas are marsupials.

Puppies should be wormed from 2 weeks of age for worms and retreated every 2 weeks until 12 weeks of age. Then they should be treated every 2 to 3 months :-)