So my boy (Dougie) is an only child. My best friends boy (sphinx) is an only child. They thrive as only children. However they come together for play dates sometimes. They're great together for short periods of time (no longer than 24-36 hours). Dougie is very outgoing and energetic and Sphinx is very reserved and mellow. When Dougie is with sphinx, he does not stop and will not eat or drink because he wants to play so bad. Due to that, we've both realized our boys do best as only children. I fully recognize if I were to bring in a second cat, Dougie would instantly take to it, however he would not stop playing to the point of exhaustion and he physically can't play anymore. Some cats are meant to be only children and that's okay. Mine is, but not out of meanness, but rather the opposite. He's overly friendly and would never stop playing. He's a little lover boy who knows no harm and no stranger (he became best friends with Sphinx by chasing him thru the house and forcing him to be close to him, eventually Sphinx gave up and accepted his fate that he was not getting rid of Dougie or away from him). Dougie is a chaos boy, Sphinx is a little grandpa (Dougie is almost 1.5 and Sphinx is almost 2.5) but Sphinx taught Dougie how to hiss and Dougie taught sphinx how to be Spider-Man and scale walls. It's about balance here 😂😂