Fairly compared to other grandchildren that she has, or just fairly compared to how you think adults should treat kids? Maybe she treats all children poorly.
If you are saying she has grandkids who she seems to favor over your child, well, they *are* her grandchildren. Your son has other grandparents who should be stepping up. He will be her step-grandchild some day, but as of now, he is just some kid who comes around when her son brings his fiance over. Sorry, but she probably won't change her attitude until after you are married.
My grandma always made a point of showing grandchild pictures and saying "And this is my ADOPTED grandchild." She never realized how rude she was being to my cousin. Your fiance's mom might be making categories in her mind. If she stays like this *after* you are married, you should say something to your husband and he should say something to her. But don't expect too much until you've actually tied the knot.
No. No no no no.
You should ABSOLUTELY expect her to treat your son the same way she treats her other grandchildren.
If you've been together long enough to be engaged, she has no excuse. You're past the point of him being "some kid that comes around when her son visits."
If it were me, I would say something to her. NOT her son. THAT is rude. Tell her that it bothers you that you feel like she treats him differently and it's not fair to him for her to do so. It is entirely possible that she doesn't realize she's doing it, but you should bring it to her attention if it bothers you this much. Don't be mean, just tell her how you feel. If she treats your son this way, who's to say you won't always feel like the red headed step child after you've married her son? It's not OK, plain and simple.
It's hard to comment for sure because while you say she treats your son harshly (bad but possibly not changeable), you don't say if he is being treated more harshly than someone else (bad and also unfair).
I know a guy who is tough and impatient with kids, including his grandchildren who he says he loves. I don't think anything the parents could say would make him change (he's actually pretty harsh with adults, too). It's not nice of him, but it's wasting breath to try to tell him to change, he is just very gruff. If she is like that, you might not ever get anywhere with her.
If you're saying she treats someone sweetly and then turns around and is immediately harsh with your son, you do have the right to call her on it, and the way to do it is to give her concrete examples of what she said that was nice to one kid, and then the same subject that was harshly handled, to your son. Otherwise she might not even know what you mean, or might not bother to stop.
If she is generally a harsh person, there is certainly no reason that you are required to be around her very much.
I TOTALLY AGREE WITH @MegiLiz if your relationship with her son has made it this far whether your son is biologically his or not if he accepts him so should she!! Point blank!
I'm in sort f the same situation...but it's reversed. ..me and my fiancee are very close to getting full rights and custody of his son and I'm filing for legal gaurdianship...my parents always think of my son and not his even to this day unless I bring him up and yet my mother in law took in my son since day one and treated him as if he were blood and she treats all her grand kids the same....so regardless. She should have more respect for ur son an has to learn to accept him it isn't fair nor right he will feel left out trust me my step son(soon to be) has ask me a y times why my mom won't take him and only take his brother..it puts me in tears I've had to put my foot down she didn't like it but if she can't accept him as her grandchild I told her she can't see any of them until she treats them all fairly...so do make it a point to say something I wouldn't be rude about it but she needs to know
I agree with MegiLiz too. I wouldn't let her treat your son poorly! That's just not fair. You and your fiance are about to be a family and whether your son is his or not, he's part of the family too. Tell her how you feel.
So this doesn't correlate to your situation exactly, but it's pretty close.
I have a 3 year old son and am now pregnant with another man's kid. From the beginning, he and his family accepted my son as if they were there all along. I Def lucked up there. But what do I do in a couple of years when the one I am pregnant with is able to start realizing that the older kid has an extra set of grandparents that he doesn't? Like I know my exes parents will never be rude to my kid, and will treat them both fair while they're together, but how do I explain his older brother going to stay with his grandparents. Or if come christmas time or birthdays or whatever the case may be, my oldest gets presents from people and he doesn't?
Not trying to jack your post, just this thought popped in my head as I was reading it.
As an actual resp ok nse to your post though, I would have already asked your man to have a talk with his mother. She doesn't have to necessarily call your kid her grandchild if she doesn't want to or is not ready to. But she could at the very least act more fair to him as he is just a child and there's no reason in being so rude towards him.