well when you do window.open
you should be assigning it a name
var winPop1 = window.open(...
var winPop2 = window.open(...
you can talk to the other windows via the parent to reload the other window like:
window.opener.winPop1.document.location.reload();
or
window.opener.winPop1.document.location.href = window.opener.winPop1.document.location.href;
Eric