I would laugh at their cheek, but would actually love it, as we don’t always get together en masse, with the gc now in their late teens/early twenties. I’d try not to make hard work of the meal, and probably cook a joint in the slow cooker, lots of vegetables and a couple of choices of pudding. Alternatively, you could ask them to muck in and bring a couple of dishes with them, to make it easier for you. I am a very undemanding mum, but my children often cook for me, as they love entertaining. Enjoy your day. 😊