To my previous post, I'll add that - strictly speaking - I'm a step-grandmother. (My husband had adult children who were no longer living at home when he and his first wife split.)
On another thread, someone asked what I had done to facilitate interaction between my (now late) husband, his daughter and grandchild...
I was a bit taken aback and tried not to rise to the bait...but it dawned on me afterwards - on top of everything else, is it seen as the [step]gran's job to facilitate interaction?
I should have thought that that was the job of all the adults in a family? (And yes, I did do my bit, though it's difficult when family members are in different countries.)
I guess that it's particularly complicated in blended families. My husband's ex had three partners apart from him. Of those, two had children and grandchildren. (Her Affair Partner was childless; she and her other two partners had been widowed when they got together.)
My husband's daughter had two stepchildren and several step-grandchildren - it was one of those situations where her daughter was younger than her nieces and nephews.
DH told me that he wanted me to find another man once he was gone - I told him that I wouldn't be doing that. In all honesty, I don't think that I could cope with the complexities of a modern day blended family again.
No one sets out to be in that situation - I think that the ideal is to have one partner or spouse for life, but things aren't always that simple.
It's only now that I've written this down that I see how convoluted things can be.