Every child at some time or another gets an imaginary friend. Given that Anna isn't in school yet and only has a few friends she knows—as opposed to her many "friends I don't know"—I expected she might have one by now.

Not yet, but as of last week she has an imaginary pet. Her name is Betty, and she's a poogle (half poodle, half beagle). I guess it makes sense. Anna loves dogs, but a dog wouldn't mix well with either our two bunnies or my mother-in-laws two cats. So Anna made up a dog.

Don't tell her that, though. Yesterday,  I made the mistake of calling her dog invisible.

"She is not invisible!" Anna replied.

I quickly corrected my error. "I meant she's invisible to everyone else. Of course, you can see her."

That seemed OK, but I hate to think how she would have reacted if I'd said "imaginary" instead.

Anyway, like most imaginary pets, Betty has some distinct advantages over a real pet. She's easy to take care of—she's housebroken and since both her pee and poop are invisible, it's easy to clean up after her. Anna has an unlimited supply of imaginary dog food, dog treats, and dog toys, and though she hasn't mentioned it yet, I'm sure Betty  gets plenty of imaginary water as well.

The biggest advantage, though, is that Betty can go with Anna everywhere. This weekend, Anna played on several inflatables, including a bounce house, a "Rat Race" obstacle course, and a slide in the shape of a sinking ocean liner. Betty got to go on every one. Last night, Anna brought Betty to see the fireworks at PK Park and she didn't get scared at all. Today, Anna brought her to the mall, where only assistance dogs and imaginary dogs are allowed. Betty played with Anna until some other kids showed up, then she sat quietly, waiting until Anna was done. Imaginary dogs are very well-behaved.

Imaginary dogs seem to grow up faster. On Saturday, Betty was a little puppy, but by yesterday she was "all grown up" and "medium sized." I'm not sure if she'll get any bigger, or smaller for that matter. She may even turn back into a puppy, or change breeds. Since I only had real dogs growing up, I'm not sure what imaginary ones can do.

Maybe by next week she'll learn to fly.