Returning Wedding/Shower Gifts

My daughter eloped right after xmas of 2005. The inlaws decided to have a small shower for the kids in May and we had a wedding reception at our house in July. Now things have soured. We have stuff that isn`t even used sitting in her old bedroom. DO WE RETURN EVERYTHING NOT USED? We`re hoping they can work things out, but I need to know what eventually might happen to all this stuff. Thanks to anyone who can help.