Very good choice to not breed.
Four is definitely not too old to neuter. There is no guarantee that the behavior will stop, but it's worth a try. He should not need to stay overnight. Neutering is a very quick procedure (<10 minutes) as long as his testicles have descended.
__________________ Crystal  , Ellie May (RIP)  , Rylee Finnegan  , and Gracie Boo🐶 |