List adapters = getChildAdapters();
log.debug("childAdapters = " + adapters);
log.debug("child = " + child);
int index = adapters.indexOf(child);
if (index < 0)
throw new StrutsException(child + " is no child of " + this);
int siblingIndex = before ? index - 1 : index + 1;
return ((0 < siblingIndex) && (siblingIndex < adapters.size())) ?
((Node) adapters.get(siblingIndex)) : null;
}