I think the objection to the term is fine, you don’t have to see yourself as a parent or your pet as your kids. It’s an imperfect analogy for familial closeness and caregiving role–im sure other terms have their advantages. I was more suggesting an explanation for why it makes sense for some people, especially those who adopt puppies. After all, parents to human children stay parents regardless of the children’s age… Which gets to the semantic hiccup behind this disagreement, there are two usages of child, one usage denotes familial relationship and social role, and one denotes age. I’m not a child, but I am the child of my parents.

Words are socially constructed, develop new meanings, and vary between cultures. Pet parent might be a new definition distinct from biological parent. Some people feel comfortable calling every family friend of their parents’ generation auntie/uncle and others find it weird because it defies their blood-relation conception of the term. That’s okay. Live and Let live.

Though, I think comparing the analogy of pets as children to treating pets as plushies says more about how you view children than anything :P