"Language is important but it's also about the specific charge of using/manipulating his child's death - which your post didn't make."
But he is using it, he used it in a speech, he's using it to make a point...
I know there are connotations in the word using that are negative - but it's not the only way it's ever used.
And a speech at a party conference is pretty much supposed to manipulate, otherwise it's a bit pointless really. In response to the questions about lord Freud's comments he was trying to stop discussing it and that experience is what he chose to draw on to do that. If he'd chosen a different experience, if he'd said, look I've spoken to out of work adults with disabilities, I don't need a lecture...that's still manipulating the discussion to try and shut it down.
Yes, obviously it's different if there's a post saying he is uncaring or didn't suffer or grieve when he lost a child that's different, that's not ok on any level.
But when he puts it out there as a piece of information relevant to an issue... I think it then should be a piece of information relevant to the issue that you should be able to say is being used or manipulated, in the same way that any other experience put out there in public as relevant to the issue would be.