1. A second animal bought as a quick replacement to help a child get over the death of a first animal.
2. On the occasion of a smaller animal where the child has less contact (i.e. goldfish, hamster, amoeba), the child does not have to know that an interpet has been used so long as the interpet looks similar to the original.
1. Oh, Sammy, we're sorry your dog Biscuit died. This dog's name is Gravy, isn't he cute?
Oh mommy, Gravy is so cute! Daddy, hurry up and cover Biscuit, he's starting to smell!!
Okay honey, you take the interpet...I mean Gravy inside.
2. Honey, did Sammy's goldfish really recover, or is it an interpet?