I have the following XML:
    <root>
 <groups>
  <group id="101">
   <number>10</number>
   <children>
    <leader id = "A" />
    <members>
     <member id="1">
     <member id="2">
     <member id="3">
    </members>
   </children>
  </group>
  <group id="102">
   <number>20</number>
   <children>
    <leader id = "A" />
    <members>
     <member id="4">
     <member id="5">
     <member id="3">
    </members>
   </children>
  </group>
  <group id="103">
   <number>30</number>
   <children>
   <leader id = "A" />
    <members>
     <member id="1">
     <member id="4">
     <member id="3">
    </members>
   </children>
  </group>
 </groups>
</root>
How can I sum the property of all the member whom id = 1 using XSL?
Thanks