She already thinks that it is normal to share your partner and not commit to one person
It is perfectly normal, not common, but not 'abnormal'. Our relationship is honest, committed and consensual, just not monogamous. The two things aren't mutually exclusive however much you are determined to think they are.
My problem wasn't with the courts judgement - there were clearly multiple safeguarding issues and an inability to care for the children properly.
My issue with both the guardian article and the independent article (and the reason for posting) was the journalists erroneous portrayal that the 'open relationship' was the cause of the children's removal, rather than the fact that there were multiple reasons for it, only one of which was linked to the fact that the parents relationship was open.
Any of these circumstances could have occurred if the mother was single, for example, and conducting her relationships in an inappropriate way regarding her children.
That an 'open relationship' in and if itself is not a reason to remove children from their parents, but failure to conduct your life in a way that was safe for the children regardless of relationship status is.