I m not sure why your son would tell you unless to shock or to get you going I m sure if we all knew some of the things that go on in others houses we would have a fit
I don’t know what a buffet is so presume it’s a little stool
You can buy special cupboard and drawer locks to keep little fingers out so maybe suggest that if he tells you any other tales or buy him some yourself and give them with a casual laugh “I saw these today and thought of young Xxx and his shenanigans” but unless it was a steak knife or carving knife which hopefully they keep in a safe place I guess it was not that bad could do more damage with a fork if he had used that and fell Drawers and cupboards are very tempting to inquisitive minds but safety is paramount at that age so I do understand your concern I hope he got a telling off for painting the stairs
I think you were right not to comment to your son unless you had said something light and smiley but certainly not a lecture
I’m finished my festival poncho