My parents are divorced and I plan on having two showers. One for each side of the family. My mother recently re-married and now I have another set of "grandparents". Is it proper etiquette to invite my mother to both showers? What about my maternal grandmothers? And finally my step-grandmother? I really don't view my step-grandmother as an important person in my life but my maternal grandmothers are very close.
I will have the same issue on step-parent recognition at my wedding and reception but I do want to do it properly.
Tyically mothers do attend all showers for their daughters. If there is a shower for the other side of the family, your mother can attend as long as all are on good terms.
We have had to walk softly these days when exes are involved. But, this is not the case here.
Inviting grandmothers is common and is a nice gesture. All step-family members are an option. In fact, unless you are close to your step-father and step-grandmother their roles for your wedding are quiet ones. If your step-father is contributing, he should be mentioned on your invitation and should be treated as a father. It is your option how you wish to honor him during the wedding and reception.
Your step-grandparent is a wild card for your wedding. It would probably be best to treat her as a grandparent though. But, again this is your option. It is just a very nice gesture.
FYI: Family members should not host your showers unless the person is in the bridal party. When family hosts wedding showers it is viewed as self-serving in most cases. So, this is a consideration.