Breeding

On important aspect of PSS is breeding your pets. Before you can breed your pets, you have to have two of the same pet (a mate for your first pet).

To get a mate, click on your pet's pen and the Buy Mate message will appear:

The mate costs the same amount as your original single pet costs.

Once you have two pets, you can breed them to make up to two babies. Click on the pen with two pets inside, and the Breed button appears.

When you go to the Breed screen, it will tell you how long it will take for your new baby pet to be made. The pet has to "grow" in the nursery. Like everything else in the game, if you don't want to wait, you can speed up the process by using Gems (either saved up, or purchased with real money).

German Shepherd takes 9 hours to "grow".

When your new baby pet is done growing, you have to go back to the nursery in order to add the new baby pet to the pen with its parents.

If you don't go back and collect the new baby pet, it will get sick.  I imagine this is similar to in RS or BS when food "spoils". In those games, you can either get rid of the food (doesn't cost anything) or unspoil the food, using Gems.  I'd imagine that in order to make your pet un-sick, you would have to use Gems, but I am not 100% on this one (and I don't want to find out, LOL).