Index: lams_common/src/java/org/lamsfoundation/lams/learningdesign/ComplexActivity.java
===================================================================
diff -u -r7f203b0b0a2e56896f7eee5367b52d1ec4db483e -r1298a23011114e3088ec0e9686e0ceac246d9a6f
--- lams_common/src/java/org/lamsfoundation/lams/learningdesign/ComplexActivity.java	(.../ComplexActivity.java)	(revision 7f203b0b0a2e56896f7eee5367b52d1ec4db483e)
+++ lams_common/src/java/org/lamsfoundation/lams/learningdesign/ComplexActivity.java	(.../ComplexActivity.java)	(revision 1298a23011114e3088ec0e9686e0ceac246d9a6f)
@@ -2,6 +2,7 @@
 
 import java.io.Serializable;
 import java.util.Date;
+import java.util.Iterator;
 import java.util.Set;
 import org.apache.commons.lang.builder.ToStringBuilder;
 
@@ -86,4 +87,20 @@
 	public void addActivity(Activity activity){
 		this.activities.add(activity);
 	}
+	
+	/**
+	 * Return the requested child activity based on the id.
+	 * @param activityId the requested activity id.
+	 * @return the child activity.
+	 */
+	public Activity getChildActivityById(long activityId)
+	{
+	    for(Iterator i = this.activities.iterator();i.hasNext();)
+	    {
+	        Activity child = (Activity)i.next();
+	        if(child.getActivityId().longValue()==activityId)
+	            return child;
+	    }
+	    return new NullActivity();
+	}
 }
\ No newline at end of file
Index: lams_common/test/java/org/lamsfoundation/lams/learningdesign/TestActivity.java
===================================================================
diff -u -r767befd47f504dca54e33fdba43785c42067eec4 -r1298a23011114e3088ec0e9686e0ceac246d9a6f
--- lams_common/test/java/org/lamsfoundation/lams/learningdesign/TestActivity.java	(.../TestActivity.java)	(revision 767befd47f504dca54e33fdba43785c42067eec4)
+++ lams_common/test/java/org/lamsfoundation/lams/learningdesign/TestActivity.java	(.../TestActivity.java)	(revision 1298a23011114e3088ec0e9686e0ceac246d9a6f)
@@ -34,8 +34,8 @@
 	private static final Long TEST_SURVEY_ACTIVITY = new Long(20);
 	private static final Long TEST_MB_ACTIVITY = new Long(19);
 	private static final Integer TEST_USER_ID = new Integer(2);
+	private static final long TEST_CHILD_QNA_ACTIVITY_ID = 22;
 	
-	
     /*
      * @see AbstractLamsTestCase#setUp()
      */
@@ -96,6 +96,15 @@
         assertEquals("verify the order of this group",1,testGroup.getOrderId());
         
     }
+    
+    public void testGetChildActivityById()
+    {
+        Activity complexActivity = activityDAO.getActivityByActivityId(TEST_SEQUENCE_ACTIVITY);
+        
+        Activity child = ((ComplexActivity)complexActivity).getChildActivityById(TEST_CHILD_QNA_ACTIVITY_ID);
+        assertNotNull(child);
+        assertEquals("verify id",TEST_CHILD_QNA_ACTIVITY_ID,child.getActivityId().longValue());
+    }
     /**
      * @see org.lamsfoundation.lams.AbstractLamsTestCase#getContextConfigLocation()
      */