diff --git a/Course3/Lab4/validations.py b/Course3/Lab4/validations.py
index b18de65a2e..d01a691546 100644
--- a/Course3/Lab4/validations.py
+++ b/Course3/Lab4/validations.py
@@ -1,5 +1,7 @@
 #!/usr/bin/env python3
 
+#!/usr/bin/env python3
+
 import re
 
 def validate_user(username, minlen):
@@ -12,13 +14,26 @@ def validate_user(username, minlen):
     # Usernames can't be shorter than minlen
     if len(username) < minlen:
         return False
+
+    # ✅ First character must be a letter
+    if not username[0].isalpha():
+        return False
+
     # Usernames can only use letters, numbers, dots and underscores
     if not re.match('^[a-z0-9._]*$', username):
         return False
+
     # Usernames can't begin with a number
     if username[0].isnumeric():
         return False
+
     return True
 
 
+# Test cases
+print(validate_user("blue.kale", 3))    # True
+print(validate_user(".blue.kale", 3))   # False
+print(validate_user("red_quinoa", 4))   # True
+print(validate_user("_red_quinoa", 4))  # False
+