Lex is being neutered tomorrow morning so I will let you know how his weight goes. He is now 9 1/2 lbs but you won't know it to look at him. The vet says it's his bones. Who knows.
My dad and husband both said that neutering will put a bit of weight on them and change their disposition. I know getting my tubes tied I put on a few pounds
. Anyways....last year we had April spayed and she did put on some weight even though she eats the same amount of food but her personality stayed the same. My old male cat Tyrant gained weight when we had him neutered but his personality stayed the same...he remained like a playful kitty down until the end.