I think I made a mistake last night by watching the film "Marley & Me." I'm not saying this because I thought the film was a waste of time, but because I have a 13-year-old, deaf, gray-muzzled Lab who can barely walk up the stairs.

I basically knew what the film was about, but I expected it to be less endearing and that it would seem removed enough from reality that it wouldn't affect my real life. But it did.

"Marley & Me," which is based on a John Grogan memoir and stars Jennifer Aniston and Owen Wilson, spans the entire life of a yellow Lab named Marley. Although the canine is the main character, the film also tells the story of John and Jenny Grogan's ups and downs as journalists, married people and the parents of three children.

Watching long periods of life recapped in an hour-and-a-half film is always eerie. It's an uncomfortable reminder that time goes by so quickly -- especially, it seems, when you have kids.

"Marley & Me" shows that the lifespan of a dog is no more than a short whistle of existence.

This weekend, my husband will build a ramp over a portion of the back stairs so our dog can have an easier time going outside, and I plan to age-appropriately talk to our kids about the inevitable passing of our pooch. I have a few books on hand and I'm ready to field questions.

I've spent so much time thinking about how my kids will handle our dog's death that I didn't realize something until watching this film last night: I'm not ready for our dog to die.