This is of course the nub of it, and of course all the issues surrounding it become more complex once there is division to be exploited between the parents, (be it benign in the sense the state has to intervene to bring some resolution, or "social engineering", if you can believe them capable of such behaviour?).
In my case, over my own daughter I'm prepared to believe in cock up, rather than design to explain the behaviour of the government employees who failed to support me, but they did cover up deliberate lying by my ex. They made their minds up as to my worth to my child in five minutes, when they had her confront me with untruths like, " I never took her anywhere interesting", (and refused to look at photographs showing the opposite to be true).
I regress though to my own situation, and although I'm guilty of doing this too often, and this thread is not about me, it obviously sticks in your mind, not least when you've met so many parents and grandparents similarly treated.

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