As said to me by my 11 year old daughter yesterday morning when her school coat wasn't in the house. My first reaction was to scoff mightily, this seeming like blatant dodging the issue tactics on her part. But after she'd gone off to school with no coat on, I did wonder whether she might have a point. Is there a practical - or maybe even an ethical - distinction between an item being lost, and its location being merely unknown?! Maybe 'lost' to her implies something being gone forever, like her last two school coats. Whereas this coat might be in some kind of holding phase, in one of maybe three possible locations, and would only be truly lost if she couldn't find it in the corner of the playground or in lost property or in the class cloakroom.
Is she being unreasonable?
(she did eventually find the coat, if that helps... it was where she left it)