diff --git a/dear_petition/petition/api/tests/test_batch.py b/dear_petition/petition/api/tests/test_batch.py
index 9505fc7b..cc87ac71 100644
--- a/dear_petition/petition/api/tests/test_batch.py
+++ b/dear_petition/petition/api/tests/test_batch.py
@@ -1,10 +1,14 @@
 import pytest
+import datetime
 
 from django.urls import reverse
+from django.utils import timezone
 from django.utils.datastructures import MultiValueDict
 
 from rest_framework import status
 
+from dear_petition.petition.tests.factories import BatchFactory, CIPRSRecordFactory, OffenseFactory, ClientFactory, OffenseRecordFactory
+
 pytestmark = pytest.mark.django_db
 
 
@@ -29,3 +33,42 @@ def test_batch_post_multiple_files(api_client, fake_pdf, fake_pdf2, mock_import)
     assert response.status_code == status.HTTP_201_CREATED
     assert mock_import.assert_called_once
     assert "id" in response.data
+
+def test_adjust_for_new_client_dob():
+    """Test that when a DOB is added or updated on the client, the batch is updated accordingly."""
+
+    batch = BatchFactory()
+    record = CIPRSRecordFactory(batch=batch, offense_date=datetime.date(2000,1,1), dob=None)
+    offense = OffenseFactory(ciprs_record=record, disposition_method="OTHER") # Conviction charge
+    offense_record = OffenseRecordFactory(
+        action="CONVICTED", offense=offense
+    )
+
+    client = ClientFactory(dob=timezone.now().date()) # Create a youngster
+    batch.client = client
+    batch.save()
+    batch.adjust_for_new_client_dob()
+
+    assert offense_record in batch.underaged_conviction_records()
+
+    batch.client.dob = datetime.date(1800,1,1) # Update the youngster to be an elder
+    batch.client.save()
+    batch.refresh_from_db() # adjust_for_new_client_dob should get automatically called in Client save
+    assert offense_record not in batch.underaged_conviction_records()
+
+    client = ClientFactory(dob=datetime.date(1800,1,1)) # Create an elder
+    batch.client = client
+    batch.save()
+    batch.adjust_for_new_client_dob()
+    assert offense_record not in batch.underaged_conviction_records()
+
+    batch.client.dob = timezone.now().date() # Update the elder to be a youngster
+    batch.client.save()
+    batch.refresh_from_db() # adjust_for_new_client_dob should get automatically called in Client save
+    assert offense_record in batch.underaged_conviction_records()
+
+    # try un-setting client to test default behavior when no DOB known
+    batch.client = None
+    batch.save()
+    batch.adjust_for_new_client_dob()
+    assert offense_record not in batch.underaged_conviction_records()