There is a little dog that lives at our house. Her name is Buttons and in human terms, she is a senior citizen. When I came into her life, she was well into middle age and, like most who reach that point, was set in her ways.

She is my stepdog. I also have three stepchildren, although none of them are children anymore. When my wife and I got married, she took my name, which is an incredible burden for someone to bear. The children kept their last name.

Then, there was Buttons.

With her advancing age, Buttons has had to make more visits to the veterinarian. Ours is a wonderful woman named Jane White, who I deeply admire. If she took human patients, I'd sign up.

Somewhere, somebody in a veterinarian's office decided dogs should share the last name of their owners. There is a prescription on our kitchen counter for Buttons Blackwood. I'm OK with that, but did anybody ask the dog?

For the first few years, Buttons and I had a distant relationship. She barked at me when I came in the house. Now, I think she has some memory lapses. If I'm gone for a day or two, she barks at me when I come home.

Should this poor old dog, who forgets me after 48 hours, have to also bear my name?

In fact, should pets have last names at all?

Lassie, who was a popular TV dog, belonged to the Martins. Little Timmy Martin was played by Jon Provost and I never heard Timmy call her Lassie Martin.

Another famous dog was Rin Tin Tin. One of the dogs that played Rin Tin Tin on TV was registered by the name Hey You. I've been called that name myself. If I had a dog with that name, a prescription for Hey You Blackwood could be mine or the dog's.

Buttons, whatever her last name is, has made herself at home in our new house. I envisioned her sleeping in the laundry room. Well, that didn't happen. She lives in our room in a little basket bed. She snores worse than I do. If my wife wakes up in the middle of the night, she gets serenaded with stereo snoring.

As long as no one upsets the routine, Buttons is quite happy at home, especially, when no one is there.

But that's not true for all dogs.

A co-worker of mine has a Siberian Husky named Salsa. I always thought a Siberian dog should have a name like Khrushchev or Solzhenitsyn.

Salsa goes to doggie day care every morning. She recently graduated from the little dog to the bigger dog classroom. Her mommy takes her dog food each day in her lunch box.

The day care center has a social hour where dog owners can meet and greet; it's called "Yappy Hour." When she comes to pick her up, the workers readily identify her as "Salsa's Mom."

Based on the way she growls at me, I don't think Buttons sees me as her daddy. I'm just that guy who occasionally takes her out to do some business and puts some food in her bowl.

If I'm gone for a few days, we just start all over again.

Harris Blackwood is a columnist for The Times. His column runs every week in Sunday Life.