This is a diffcult situation, because of the children involved (hers and yours).

You didn't mention how much your gf's baby daddy is involved in the boy's life, but I get the impression that he must be pretty involved (particularly if your gf thinks that this man will follow his son across country in order to parent him). So I'm not a big fan of breaking the connection between an actively involved father and son. (And the fact that your gf has sole physical custody doesn't mean everything....I'm assuming there is no formal custody agreement, as she and the baby daddy were never married.)

That said, I think there's a way to accomplish what you'd like (to make a family with your gf) - but you're probably not going to like my suggestion, cause it involves slowing the process way down.

I think it would be great if you and your gf would do some serious pre-marital counseling - not because you're having problems, but just so you can really discuss the kinds of topics that most people in the throes of romantic love dismiss...like religious beliefs; having more children; working mom vs stay-at-home mom; how to successfully blend your families; how to deal with your exes, how she'll cope with separating from her family (I'm assuming her family is in Kansas); how to manage long-distance relationships with her boy's grandparents, etc. Let's face it - there's a lot to work out.

If you take the time to do the work, and still find that you really want to make a family together, then I suggest working with the baby daddy to coordinate the move (rather than surprising him with an announcement). He'll probably be more inclined to cooperate if you and your gf treat him like a partner in this whole situation, because that's what he is. He'll have a choice to make: respond like an adversary, or like a teammate. It will be so much better for everyone if he decides to be a teammate.

That said, in this economy, it's probably going to take him a while to find a job (although that's not necessarily true, depending on his profession). That's going to slow things down as well. Again, if he's a teammate, then your future wife is not going to be worried about allowing him to take her son back to Kansas to visit his paternal grandparents every so often. I think you'll really find it worth it to take your time, and proceed at a pace that everyone is comfortable with.

And that leads me to my last point - your kids. They need some time to adjust to this idea of a new parent and a new brother, as well. I don't know what your relationship is with your ex, but that's another relationship that has to be managed (it's in the best interests of your children to make the integration of your gf into your family as painless as possible).

So....my recommendation is to continue commuting, skyping, texting, telephoning, etc., with your gf while you lay the groundwork for this major transition in everyone's lives. I know you don't want to wait (and you could always choose not to) - but this is complicated, and complicated situations take more effort and more patience to handle. Good luck.

Great Feedback... thank you!!!!
Let me try to address a few things.
Baby Daddy is not involved. However, he loves his boy very much and is very protective of him. He's told Mom that he doesn't want any men (besides himself) around his boy. So, a little unrealistic as well if you ask me...not to mention controlling.
There is a formal and uncontested agreement between the two parents and the courts. He gave her everything, no battle. Dad only gets overnights if mom goes out of town on business. He also gets every other weekend during the day only. Sometimes she'll play sports during the week, so he'll get Daddy time then too.
I am ALL FOR Pre Marital Counseling... all aspects of it!!
My ex has a live in boyfriend with his own children in the mix, so, my kid's have exposure to our type of potential situation as well.
Trips to see grandparents would be welcomed and encouraged.
I agree that it needs time and lots of work. We've already looked into Montessori schools here to make sure mom was happy with moving her lil man into a healthy and nurturing environment here in Austin.

Good advice, Honey!
OP, the father of your girlfriend's son sounds very controlling. I wouldn't want to touch that with a 10 ft. pole, so good luck! I totally agree with getting pre-marital counseling and I'd add that it's not healthy for kids to see all kinds of "new mommies and daddies" come into and out of their house. I would caution you against getting so excited that you make promises to your kids that don't come through. (Like that you'll get a puppy as soon as new-mommy moves in or even that this person is your new mommy and you get a new brother.) Your job is to protect your family against everything, even potential new family members. So make it official, do it the right way, and never let them doubt that their parents love them no matter where they are.

And as far as too soon... I think you need to let the novelty wear off a little before jumping in. I mean, she already told you she'd move for you?! Really? I'm single with no kids and I told my boyfriend of nearly 2 years that I wouldn't dream of moving for him without a ring and a date! It would take a lot more to uproot a family! If you can still say that you love her and want to grow old with her after your second really big argument, it's probably more than just a feeling. So good luck with whatever you decide to do!

If you love her then ask her to marry you. Sounds like you have a great relationship and are both old enough and mature enough to know what you're doing. As far as her boy goes let the dad move near her then. He never married her and she has final say on everything now. So she has the right to do that and live her life with you. I hope she knows how great it is to have a real man in her life and a real engagement ring from you. She deserves it.