I let my child come up with the idea of the cats being her siblings, which she did in time, but I've never called them my offspring. I thought it was weird when people said, “This is Smiley. He's 15, and he's my only child,” which was often followed by a chin-scratch of the pet in question and an “Aren'tcha, my boy?” But we're all guilty of anthropomorphizing around here, I know. We are always asking our daughter to back off on certain behaviors because “He doesn't like that,” or we simply know things from experience: “Cats like to chase a toy you move just out of sight. They don't like it when you run at them with the toy.”
And our youngster insists that our tolerant boy-cat, who, like the cat in the new children's classic, Olivia, by Ian Falconer
"When she got up, she moved the cat
And moved the cat
And brushed her teeth"
just lets her ferry him from floor to lap to couch. The other day I had to tell her again she can't ride him. He's a scant 15 pounds; she's 50. Plus, it's inappropriate.
But our dear gorgeous gray cat loves us all and lets us be who we are, enthusiastically accompanying us on our bumblings through daily life and love. He has a fragile peace with our ancient crone of a kitty, the true alpha kitty, that little black scaredy-cat who seemed so fragile but grew into the hardiest of the bunch, now about 100 in people years. She is the grande dame, reigning over our bedroom. She sleeps in the trench between us on top of the bed (snug but still scaredy), while the gray boy sometimes sleeps where he can see who's in the yard, or sometimes joins us all, sleeping in his spot at the foot of the bed, or yowls at critters or longings only he hears at those hours.
(That last was an accidental but appropriate insertion while I was petting the gray cat, and made me laugh so much I left it in there.)