Sister in law pregnant/ -Grandma treats us different and unfair.

my sister in law is pregnant, we have never had a close relationship, shes always disliked me for unknown reasons.. anyways i have two kids and their grandma never showed up to any of their baby showers, hardly gets them anything or bother to visit but a couple times a year and we live right down the road. But now that she is pregnant grandma is buying her pretty much everything she needed for the baby.. why did she not do that for her son like she is doing for her daughter? She not only showed up for the baby shower she planned it and evrything.. and i have boys and shes having a girl, she is making the girl the top of the world like my boys are nothing.. shes like super excited and was never this excited for either of my boys..

i just don’t understand and needed to vent a little.. i dony want to say anything or cause any drama but it is depressing me a lot. Why is her son always last? and now her grandchildern are being treated same way last when it comes to her daughter and future granddaughter.

Also: my boys refer to her as grandma and know her as that but she is always trying to be called something different and now my sister in law is trying to get us to change what we call her so her kid can call same thing🙃