Ex Wants To Know What We Are Getting Kids for Xmas

The ex wants us to tell her what we are getting my stepkids for Christmas. However, she won't let us know what she's getting them. We've tried to coordinate with her from the very beginning (13 years now) so we wouldn't duplicate gifts but she refused. However, she told my stepdaughter recently that we are to let her know what we are getting them. Yeah, sure. It's a "control" thing for her. Why would we do that when she's refused to do the same?