My kids know “Siri” as simply a computer they can talk to. They think she’s basically a robot. Mine are 6, 5, 3. Since we use HomePods everywhere they interact with them really just like they would another UI but haven’t associated Siri with a person. It’s generally some variation of playing music or turning on HomeKit stuff. But they aren’t trying to have conversations. To them is just an iPad with no screen.