Why You Accidentally Call Your Relatives by Your Dog's Name, But Not Your Cat's

That person who lives in your house--the one that you've known all of his life--what's his name? Precision is difficult, so just run through the roster and see what sticks.
We've all done this before: call one family member by another relative's name. You may even address your husband or child with your dog's name.
But not your cat's name.
Why? Futurity summarizes research from a Duke University doctoral student named Sparky Samantha Deffler. She explains that it's because dog names have greater significance in families:

In addition to mixing up sibling for sibling and daughter for son, study participants frequently called other family members by the name of the family pet—but only when the pet was a dog. Owners of cats or other pets didn’t commit such slips of the tongue.
Deffler says she was surprised how consistent that finding was, and how often it happened.
“I’ll preface this by saying I have cats and I love them,” Deffler says. “But our study does seem to add to evidence about the special relationship between people and dogs.
“Also, dogs will respond to their names much more than cats, so those names are used more often. Perhaps because of that, the dog’s name seems to become more integrated with people’s conceptions of their families.”