diff --git a/java/Chapter 4/Question4_7/QuestionB.java b/java/Chapter 4/Question4_7/QuestionB.java
index fe4854aa..7b741113 100644
--- a/java/Chapter 4/Question4_7/QuestionB.java	
+++ b/java/Chapter 4/Question4_7/QuestionB.java	
@@ -15,7 +15,7 @@ public static TreeNode commonAncestorHelper(TreeNode root, TreeNode p, TreeNode
 		}
 		boolean is_p_on_left = covers(root.left, p);
 		boolean is_q_on_left = covers(root.left, q);
-		if (is_p_on_left != is_q_on_left) { // Nodes are on different side
+		if (is_p_on_left != is_q_on_left || root == p || root == q) { // Nodes are on different side
 			return root;
 		}
 		TreeNode child_side = is_p_on_left ? root.left : root.right;