Hello, I'm Alicia. Thanks for your question, I'm happy to help you today. I do not think it is unrealistic for you to ask him to ask his son to move out, especially given his age and given the fact that you want to establish a comfortable home and house and a new life for you and your spouse to be. However, I think it's important to be diplomatic, because this could be a real bone of contention between you and your spouse (as it seems it may have already become -- you don't want to inflame the situation further by making demands, because he may likely rebel if he feels "forced" to do something, so try to keep that in mind when you broach the topic.) It may take some time for him to see eye to eye with you on this one, but I think you need to stay firm yet kind and compassionate (to a point). And it obviously also depends on circumstances (to a point), for example, whether the son is able to financially support himself and if not, how is he going to get to that point within a certain time frame. I would suggest that when you speak to your spouse, you come from an "I" standpoint and focus on your feelings, instead of, for example, blaming him or his son. You may have to repeat yourself a number of times and on different occasions -- and it's also possible that you might have to compromise. I would suggest agreeing on some sort of time frame and say something like, "When we get married and live together, I'd really like the chance for us to start our new life together on our own. I know there are certain considerations but it seems to me that perhaps it's time that "Jimmy" thinks about getting his own place. I obviously care about Jimmy very much, but it's also important for him to be able to stand on his own two feet -- we won't be doing him any favors if we enable him and let him live here forever; he's an adult now and needs to be able to take care of himself. I know it's not easy but maybe we could agree on a reasonable time frame for Jimmy to start looking for his own place." I'd suggest saying something like that. If he's able to support himself, I would suggest a six-month time frame max. When you do move in and if Jimmy is still there, you do need to try to use a bit of diplomacy -- Jimmy is still his son and you are now going to be a part of the same family. So you want to include him and make him feel like you are on his side, not that you're trying to kick him out and that you want his dad all to yourself (obviously I realize this isn't where you are coming from). Agree with your new spouse on certain house rules -- whatever you both feel are appropriate. Make sure Jimmy pitches in and helps out (with chores, with finances, again, if he's able). Insist that everyone treat each other with respect. If there is a problem between you and Jimmy, it's important that you and your new spouse are on the same page -- he needs to back you up on these types of issues. It can be a tricky road to navigate but it sounds like you have a really strong and positive relationship with your new spouse so if this is the only thing you disagree on I think you will be able to work it out. I wish you all the best.