I'm not sure I could put a "child" age on any of the cats I've had, except to say that they do tend to behave in fairly predictable ways depending on their life circumstances just as most children tend to be fairly predictable to adults who have experience with kids. But I agree, they definitely have their own life and interests and personalities. Our previous cats were twin brothers but wow they had different personalities and interests. One was very independent and wanted to explore everywhere and be in control. The other really just wanted to spend all his time snuggling with me and didn't really care about anything else. Except food. He REALLY cared about food. His brother, not so much. Anyone that says cats don't have personalities has never lived with one for any length of time.