One of my DCs has a friend (aged 9) who has told us he is allowed to watch some violent films at home. Recently when they were choosing a film to watch, this child pooh-poohed my DC's child choices as boring, suggested watching Blade Runner (rated 15) instead and described a scene from the film where someone had his stomach cut out. Fortunately my DC is a bit of a wuss when it comes to anything scary and said no, but just the conversation has scared him.
I need to raise it with the mum, as I think it's way too early for this kind of film, but I don't want to cause conflict or criticise someone else's parenting. How should I approach this?