[mcg1969]

In that case, maybe we should get rid of pacemakers, heart surgeons and organ transplants...

Fair point, except you can recover from such operations to the point that you are automomous and relatively pain free. In this case, not only is the life support causing the child significant pain, but as I read the description of the condition, even standard life support will fail eventually.

If this mother were causing an otherwise healthy child this much pain, on a continuous, ongoing basis without any sign of relief, we'd lock her up.

[Frumious Bandersnatch]

As a disclaimer, I'd like to indicate that I don't know the other side's position.

That said, to use pain (a very subjective issue) as a measure of whether a person is to live or not is not good. In that case, why not just let those who would suffer serious pain from being in an automobile accident die?

Secondly, in this case, it may be propaganda, but the proponents indicate that they don't believe the child is in pain.

So, in either case, I'd say that the pain thing is a strawman. You'll have to come up with something better than that.