I sometimes compare my pets to someone's kids because the person is annoying me about their kid. I, as a person with no children, am usually bored witless by people talking about their kids (except in small, special situation, doses-such as the kid winning a nobel prize or something extremely terrible that the person needs to tell). But often if I am bringing up my pet in a like manner as with someone's kid-it means I am trying my best to relate to the person.