Those are separate concepts: we should not condemn children for their parent’s crimes but that doesn’t mean that we should forget that those crimes happened.

In this case it’s especially important because those children were treated very differently from their siblings: a slave owner’s fully white children had full status in society and lived in relative luxury but those borne by slaves inherited their mother’s status. Apologists try to claim that some relationships were consensual but it’s hard to reconcile that with the treatment of any resulting children.

> we should not condemn children for their parent’s crimes but that doesn’t mean that we should forget that those crimes happened.

But then what do you propose to do about it? All of those people are dead. We can't bring them back to life and punish them.

> In this case it’s especially important because those children were treated very differently from their siblings

It was no doubt a very important distinction to the children. I wouldn't want to have to argue it was a very important distinction to modern day descendants seven generations later when that ancestor represents less than 1% of their ancestors from that many generations ago.

And the usual argument is to want to assign guilt if you benefited from a bad thing one of your ancestors did. But having existence is a pretty huge benefit, which makes that argument taste quite sour.

It’s not always 7 generations ago - there was a guy living here until a couple years back whose father was born in slavery - and it didn’t end instantly with the Civil War, or the demise of Jim Crow, or the Civil Rights movement — things like redlining ran into the 1970s and police violence and job discrimination never really stopped. White people can say it ended in the civil war era but there are plenty of people who know they still have to spend time thinking about risks their white peers do not.