My 1 year old neutered male cat has been singing the song of his people nightly, starting around 0200. It’s actually more a chirp than a meow, but he doesn’t stop until the sun comes up. He isn’t locked out of the bedroom, food and water needs are met, litter is clean, etc. He doesn’t do this during the day. He seems to keep these shenanigans confined to the hallway or the bedroom. He just walks around chirping with the occasional half meow.The only thing that seems to stop him is if I kick his brother (littermate and best friend) out of my bed and lock them both out of the bedroom, which makes HIM sad. Choir boy is happy to sleep in our bed any other time of day, with or without human or feline companions, so it’s not like he wants his brother out of the room because he himself is uncomfortable in there.I should add that there have not been any food, litter, family dynamic, or even furniture changes. Nothing new in his world. What gives?!