Responsible adults do not put children in mortal danger...
Oh for God's sake. Nobody's putting kids in "mortal danger". Nobody participating in the trials died. Or, far as I know, had any problems.
Here's the real story: you and other anti-vaxxers failed in your efforts to talk large numbers of people out of getting vaccinated, because the vaccines don't cause problems for statistically significant numbers of people.
So now the anti-vaxxers need to move the goalposts. And they've risen to the occasion, raising the scary specter of entirely made-up long-term dangers. Why do you suggest such dangers exist? When have people who've taken ANY vaccine developed problems years later, as a result of that shot?