使用XPath,如何去取得指定的节点的下一个兄弟节点？

Question

<AAA> 
          <BBB> 
               <CCC/> 
               <DDD/> 
          </BBB> 
          <XXX> 
               <DDD> 
                    <EEE/> 
                    <DDD/> 
                    <CCC/> 
                    <FFF/> 
                    <FFF> 
                         <GGG/> 
                    </FFF> 
               </DDD> 
          </XXX> 
          <CCC> 
               <DDD/> 
          </CCC> 
     </AAA> /AAA/XXX/preceding-sibling::*