Welcome to YT! Can't wait to see pics of your little guy. First I would reccomend getting him neutered, unaltered dogs can be overly protective and dominant. Neutering really does have a lot of benefits and really they are only affected for a day or two usually, it is not a big deal and you will be glad you did it.
Does your little guy go to the dog park? I would get him used to being around other dogs first. When I brought home my girl dog my boy dog Chibi was 4yrs old and had been an only dog his whole life. I was very worried he would be jealous, and he was a little bit but after an adjustment period they became good friends. Just make sure you let Riley know he will always be your number 1
