How the church handles heresy: Probably not what you think

A nun in Spain is enjoying the media limelight; probably a bad thing (look up what happened to the Singing Nun). So she's shooting her mouth off: "Mary wasn't a virgin!" This is from a tabloid but still.

I'm not her bishop but I would start the proceedings against heresy. Warn her, and if she persists, throw her out.

Our holy mother the church doesn't handle heresy like our Protestant hosts in