Our emotional response to our children's stories is based on our life experiences and our position as an adoptive parent. It does not necessarily reflect how our children will feel about it.
I think it is really hard talking to dc about their birth family.
I think that where we bring up dc to understand that verbal abuse, physical abuse, not caring for a child whom you are responsible for, the reasons behind the PANTS rule, etc, are not okay, then our dc will inevitably at some point (usually quite young ime) make connections with the fact that their birth parents did things which were not okay, and have complex feelings about this, and ask things like "are my [birth parents] bad?" which might also mean "am I bad?"
I think that how we respond is going to be really pivotal to how well the child can recover, how well they understand, so that they don't internalise shame or blame and so that they feel they have choices and are not defined by their history.
I also think that adding to difficulties for parents is that where dc love their birth parents our visceral reaction sometimes will be that they shouldn't but in fact it is important to validate and explain that it is possible to love a birth parent while also understanding the aspects of that person's behaviour which are not okay or feel they need to copy it. Usually there will be a mix of "good" and "bad" in the birth family. I think that in this way, where children love their birth parents they can also be helped to understand problems and how to do things differently, it isn't a question of children putting birth parents on a pedestal which I think is the out of date - and very unhelpful - way of looking at it.
As I say I think it is a difficult subject matter.