Regarding the mini wives situation, can a lot of it not be put down to pure jealousy on the complainant's part? (Massive generalisation alert).
I came across a lot of it in another situation, my step-sister. According to her our father preferred her, hated me, it wasn't her mother keeping him from me and my half siblings under threat of being thrown out of her house if he visited us (oh yes it was, I heard it from the horse's mouth!), it was all because we weren't his family now, she was.
My stepmother's view is that we other children (all fully grown adults living miles away and not dependent on dad or in their face) are an imposition in her family life and that our father's family is not all of us but just her, her own DC and the one DC which she and my dad have together.
We older siblings are bemused, angry and indignant in equal measure.
The result is, after years and years of this sort of reaction from SM, that she and dad have separated, dad is old and very ill now, and she, her own DC and the one they had together, now all adult, have abandoned him. Guess who's still there picking up the pieces and trying to reassure a very ill, frightened old man with alzheimers?
The (long) point I'm trying to make is to reaffirm what has already been said. There are a lot of DSC out there who are being vilified for spiteful reasons. Yes there are a lot of spiteful DSC out there too, but it's hard to accept that younger DSC are really out to get the SP and not just plain confused, upset and torn between two families.
Perhaps MN needs a stepchildren's board as well as a step parents one?