The other day on the Tube, I saw the cutest dog. It was a brown Labrador puppy, accompanying a sight-impaired man through the station… although the man seemed to be guiding the dog more than the dog was guiding him.

“Awwww, I want a dog,” I thought to myself. But if there is one thing my parents drummed into me growing up, it was the pets are a Serious Responsibility, to be taken on only when you are planning to live on a single continent for the duration of their lifespan. You can’t get rid of a dog any more than you can get rid of a child. It’s a member of the family.

But I don’t know when I’ll next be in the position to commit to a single home (or animal) for a decade.

“Oh well, I can get a dog when I’m in my fifties,” I reassured myself, picturing a future of dog walks and tossing balls in the garden.

Perhaps this is what they mean when they say you can have it all, but not at the same time.