Gary's blog discusses how parental behaviours are used to disrrupt their children's lives and suggests strategies for dealing with that.
When Children Become Pawns in the Parental Custody Dispute
Some issues between separated parents are unimaginable. I have heard stories of children coached to call the other parent names; to misbehave; to not eat their food; to be mean to step-siblings. Indeed, over the years, I have interviewed children who have told me that and worse.
Some parents in a bid to curry favor with their child will actually let them eat junk food as they want; miss school; stay out late; use drugs or drink alcohol or otherwise do as they wish just to make the reasonable parenting of the other parent seem inappropriate.