diff --git a/bin/trees/FamilyTree$TreeNode.class b/bin/trees/FamilyTree$TreeNode.class
index 0c64bab..7ba63e2 100644
Binary files a/bin/trees/FamilyTree$TreeNode.class and b/bin/trees/FamilyTree$TreeNode.class differ
diff --git a/bin/trees/FamilyTree.class b/bin/trees/FamilyTree.class
index 2999acb..dc5e392 100644
Binary files a/bin/trees/FamilyTree.class and b/bin/trees/FamilyTree.class differ
diff --git a/bin/trees/LanguagesTree.txt b/bin/trees/LanguagesTree.txt
new file mode 100644
index 0000000..138d661
--- /dev/null
+++ b/bin/trees/LanguagesTree.txt
@@ -0,0 +1,13 @@
+Indo-European:Anatolian,Indo-Iranian,Greek,Italic,Celtic,Germanic,Armenian,Tocharian,Balto-Slavic,Albanian
+Anatolian:Hittite,Luwian,Lycian,Lydian
+Indo-Iranian:Indo-Aryan,Iranian,Nuristani
+Indo-Aryan:Sanskrit,Hindi,Urdu,Bengali,Punjabi
+Iranian:Persian,Kurdish,Pashto
+Greek:Ancient Greek,Modern Greek
+Italic:Latin,Romance
+Romance:Italian,Spanish,French,Portuguese,Romanian
+Celtic:Irish,Scottish Gaelic,Welsh,Breton
+Germanic:English,German,Dutch,Swedish,Norwegian,Danish,Icelandic
+Balto-Slavic:Baltic,Slavic
+Baltic:Lithuanian,Latvian
+Slavic:Russian,Polish,Czech,Ukrainian,Serbian,Bulgarian
\ No newline at end of file
diff --git a/src/trees/FamilyTree.java b/src/trees/FamilyTree.java
index 0d72bd2..18fc2e4 100644
--- a/src/trees/FamilyTree.java
+++ b/src/trees/FamilyTree.java
@@ -7,21 +7,21 @@
 
 public class FamilyTree {
 
-    private static class TreeNode {
-        private String name;
-        private TreeNode parent;
-        private ArrayList<TreeNode> children;
+    private static class TreeNode<T> {
+        private T data;
+        private TreeNode<T> parent;
+        private ArrayList<TreeNode<T>> children;
 
-        TreeNode(String name) {
-            this.name = name;
+        TreeNode(T data) {
+            this.data = data;
             children = new ArrayList<>();
         }
 
-        String getName() {
-            return name;
+        T getData() {
+            return data;
         }
 
-        void addChild(TreeNode childNode) {
+        void addChild(TreeNode<T> childNode) {
             // Add childNode to this node's children list. Also
             // set childNode's parent to this node.
             children.add(childNode);
@@ -30,15 +30,15 @@ void addChild(TreeNode childNode) {
 
         // Searches subtree at this node for a node
         // with the given name. Returns the node, or null if not found.
-        TreeNode getNodeWithName(String targetName) {
+        TreeNode<T> getNodeWithData(T targetData) {
             // Does this node have the target name?
-            if (this.name.equals(targetName))
+            if (this.data.equals(targetData))
                 return this;
                     
             // No, recurse. Check all children of this node.
-            for (TreeNode child: children)
+            for (TreeNode<T> child: children)
             {
-                TreeNode result = child.getNodeWithName(targetName);
+                TreeNode<T> result = child.getNodeWithData(targetData);
                 if (result != null)
                     return result;
             }
@@ -50,9 +50,9 @@ TreeNode getNodeWithName(String targetName) {
         // Returns a list of ancestors of this TreeNode, starting with this node’s
         // parent and
         // ending with the root. Order is from recent to ancient.
-        ArrayList<TreeNode> collectAncestorsToList() {
-            ArrayList<TreeNode> ancestors = new ArrayList<>();
-            TreeNode current = this.parent;
+        ArrayList<TreeNode<T>> collectAncestorsToList() {
+            ArrayList<TreeNode<T>> ancestors = new ArrayList<>();
+            TreeNode<T> current = this.parent;
             while (current != null) {
                 ancestors.add(current);
                 current = current.parent;
@@ -65,15 +65,15 @@ public String toString() {
         }
 
         private String toStringWithIndent(String indent) {
-            String s = indent + name + "\n";
+            String s = indent + data + "\n";
             indent += "  ";
-            for (TreeNode childNode : children)
+            for (TreeNode<T> childNode : children)
                 s += childNode.toStringWithIndent(indent);
             return s;
         }
     }
 
-    private TreeNode root;
+    private TreeNode<String> root;
 
     //
     // Displays a file browser so that user can select the family tree file.
@@ -122,12 +122,12 @@ private void addLine(String line) throws TreeException
         // Find parent node. If root is null then the tree is empty and the
         // parent node must be constructed. Otherwise the parent node should be 
         // somewhere in the tree.
-        TreeNode parentNode;
+        TreeNode<String> parentNode;
         if (root == null)
-            parentNode = root = new TreeNode(parent);
+            parentNode = root = new TreeNode<>(parent);
         else
         {
-            parentNode = root.getNodeWithName(parent);  //There's a method in Node that searches for a named node. 
+            parentNode = root.getNodeWithData(parent);  //There's a method in Node that searches for a named node. 
             //??? If the parent node wasn't found, there must have been something wrong in the 
                 //data file. Throw an exception.
         }
@@ -135,7 +135,7 @@ private void addLine(String line) throws TreeException
         // Add child nodes to parentNode.
         //?? For each name in childrenArray, create a new node and add that node to parentNode.
         for (String name : childrenArray){
-            TreeNode node = new TreeNode(name);
+            TreeNode<String> node = new TreeNode<>(name);
             parentNode.addChild(node);
         }
     }
@@ -148,26 +148,26 @@ private void addLine(String line) throws TreeException
     // of the root is 0. The
     // depth of the root's immediate children is 1, and so on.
     //
-    TreeNode getMostRecentCommonAncestor(String name1, String name2) throws TreeException
+    TreeNode<String> getMostRecentCommonAncestor(String name1, String name2) throws TreeException
     {
         // Get nodes for input names.
-        TreeNode node1 = root.getNodeWithName(name1);        // node whose name is name1
+        TreeNode<String> node1 = root.getNodeWithData(name1);        // node whose name is name1
         if (node1 == null)
         {
             throw new TreeException("there is no node with name of " + name1);
         }
-        TreeNode node2 = root.getNodeWithName(name2);        // node whose name is name2
+        TreeNode<String> node2 = root.getNodeWithData(name2);        // node whose name is name2
         if (node2 == null){
             throw new TreeException("there is no node with name of " + name2);
         }
         
         // Get ancestors of node1 and node2.
-        ArrayList<TreeNode> ancestorsOf1 = node1.collectAncestorsToList();
-        ArrayList<TreeNode> ancestorsOf2 = node2.collectAncestorsToList();
+        ArrayList<TreeNode<String>> ancestorsOf1 = node1.collectAncestorsToList();
+        ArrayList<TreeNode<String>> ancestorsOf2 = node2.collectAncestorsToList();
         
         // Check members of ancestorsOf1 in order until you find a node that is also
         // an ancestor of 2. 
-        for (TreeNode n1: ancestorsOf1)
+        for (TreeNode<String> n1: ancestorsOf1)
             if (ancestorsOf2.contains(n1))
                 return n1;
         
@@ -183,8 +183,8 @@ public static void main(String[] args) {
         try {
             FamilyTree tree = new FamilyTree();
             System.out.println("Tree:\n" + tree + "\n**************\n");
-            TreeNode ancestor = tree.getMostRecentCommonAncestor("Bilbo", "Frodo");
-            System.out.println("Most recent common ancestor of Bilbo and Frodo is " + ancestor.getName());
+            TreeNode<String> ancestor = tree.getMostRecentCommonAncestor("Bilbo", "Frodo");
+            System.out.println("Most recent common ancestor of Bilbo and Frodo is " + ancestor.getData());
         } catch (IOException x) {
             System.out.println("IO trouble: " + x.getMessage());
         } catch (TreeException x) {
diff --git a/src/trees/LanguagesTree.txt b/src/trees/LanguagesTree.txt
new file mode 100644
index 0000000..138d661
--- /dev/null
+++ b/src/trees/LanguagesTree.txt
@@ -0,0 +1,13 @@
+Indo-European:Anatolian,Indo-Iranian,Greek,Italic,Celtic,Germanic,Armenian,Tocharian,Balto-Slavic,Albanian
+Anatolian:Hittite,Luwian,Lycian,Lydian
+Indo-Iranian:Indo-Aryan,Iranian,Nuristani
+Indo-Aryan:Sanskrit,Hindi,Urdu,Bengali,Punjabi
+Iranian:Persian,Kurdish,Pashto
+Greek:Ancient Greek,Modern Greek
+Italic:Latin,Romance
+Romance:Italian,Spanish,French,Portuguese,Romanian
+Celtic:Irish,Scottish Gaelic,Welsh,Breton
+Germanic:English,German,Dutch,Swedish,Norwegian,Danish,Icelandic
+Balto-Slavic:Baltic,Slavic
+Baltic:Lithuanian,Latvian
+Slavic:Russian,Polish,Czech,Ukrainian,Serbian,Bulgarian
\ No newline at end of file