“Grandma, what’s time travel?” Walter asks, for the third (or maybe the five hundredth) time. I’m dropping the kids off with my mom before going to work, and she mentioned something about time travel while talking about going to the Renaissance Festival with my brother. My three-year-old is still learning not to interrupt grown-ups unless it’s an emergency.

“Well,” my mom says, “if you were to get in your car and go somewhere—like to your house—that’s regular travel. And time travel is…” She pauses, trying to figure out how to explain time travel to someone who really doesn’t even understand the concept of time. She looks over at me and smiles. “Well, if you were to get in a DeLorean…”

She finally settles on the explanation that time travel would be going back to the day Walter was born so we could see him as a tiny little baby again.

“Oh,” Walter says, as if he understands perfectly. “If I get in the car, and go to my house, and turn on the robot vacuum, that would be time travel.”

My son is equally terrified of and obsessed with Babette, our robot vacuum. When Walter was a baby I asked for a robot vacuum for my birthday, and my husband delivered. I hate vacuuming (I would much rather fold laundry,) but with two cats shedding hair and tracking litter all over the house, it’s something that needs to happen regularly. Now that I have the robot vacuum, it’s easy to just turn Babette on as I’m leaving the house and let her do a “good enough” job cleaning the floors.

We tell Walter that no, going to the house would just be regular travel, not time travel, even if the robot vacuum is involved. I say time travel would be going back to the time we came home and found Babette stuck under Daddy’s computer desk. (That incident is one of my son’s core memories.)

I’m not sure what triggered Walter’s fear of Babette. I think it has something to do with the way she comes off her dock (sometimes when he doesn’t expect it) and moves around by herself. Walter sometimes asks me to draw pictures of robot vacuums on their docks when we’re coloring. He also tells people, “Sometimes I’m scared of Babette,” leaving me to fill in the context that Babette is our robot vacuum. He even offered this piece of information to our pastor while we were up at the altar for communion one Sunday.

It’s time for me to go to work. I give Walter a hug and a kiss (and an extra kiss, and a nose kiss.) I give Phoebe a little squeeze and a kiss on the forehead.

My daughter is less than two months away from her first birthday, and it occurs to me that soon we won’t have a baby in the house anymore. She’s already walking. I just bought her first pair of shoes: navy blue Stride Rites with sparkly silver stars and lightning bolts on them—very sporty. The first time she tried them on she immediately sat down on the floor, but she’s gotten used to them now after a few days of practice. Even though she’s walking (and has been for a few weeks) I refuse to think of her as a toddler until after she turns one.

“Bye-bye!” I say, waving from the doorway of my parents’ house. “Bye-bye, Walter. Bye-bye, Phoebe.”

This good-bye routine is mostly for Phoebe. She just learned to wave, and I’m trying to get her to wave back at me. It works. Her face lights up and she uses her whole arm to wave to me. It’s adorable and exciting to watch her learn that she can communicate with me. I could spend all day just waving back and forth with her, but I’m already running a few minutes late. I get in my car and think about time traveling back to the day my son was born.

Time travel is “just pretend,” my mom told Walter (though my brother the physicist could probably explain how it’s theoretically possible.) I don’t have a time machine, but I do have pictures, videos, and stories recorded in my journals. Remembering is a bit like traveling back in time. Someday, from the future, I’ll look back on this season—of questions about the robot vacuum, of baby steps and babbling and good-bye kisses, of dropping off the children with Grandma every morning, of toys and books that have to be picked up before Babette can clean the floors, of diaper bags and pumping and potty-training—and wonder how it only lasted a moment.

This post is part of a blog hop with Exhale—an online community of women pursuing creativity alongside motherhood, led by the writing team behind Coffee + Crumbs. Click here to view the next post in the series “Moment in Time”.