Should the wishes of parents be overruled to save a child?

Em

For example, a child needs a blood transfusion or transplant, but because of the views/beliefs of the parents, they won’t allow this to happen. There is no medical reason why not, it’s just that they don’t agree with it. Ultimately the child will die.

Should the State/Government/Social Services or whoever step in and overrule the parents and go ahead with the treatment anyway? Or respect the wishes of the parents, knowing that it will result in the death of the child who has no say in the matter?

(Note- this is not my idea, it was an old storyline on a long running British medical soap some years ago)