diff --git a/care/facility/api/serializers/patient.py b/care/facility/api/serializers/patient.py
index 32e378dc9a..b3a88b21e3 100644
--- a/care/facility/api/serializers/patient.py
+++ b/care/facility/api/serializers/patient.py
@@ -500,6 +500,21 @@ class Meta:
         exclude = ("patient_note",)
 
 
+class ReplyToPatientNoteSerializer(serializers.ModelSerializer):
+    id = serializers.CharField(source="external_id", read_only=True)
+    created_by_object = UserBaseMinimumSerializer(source="created_by", read_only=True)
+
+    class Meta:
+        model = PatientNotes
+        fields = (
+            "id",
+            "created_by_object",
+            "created_date",
+            "user_type",
+            "note",
+        )
+
+
 class PatientNotesSerializer(serializers.ModelSerializer):
     id = serializers.CharField(source="external_id", read_only=True)
     facility = FacilityBasicInfoSerializer(read_only=True)
@@ -515,6 +530,13 @@ class PatientNotesSerializer(serializers.ModelSerializer):
     thread = serializers.ChoiceField(
         choices=PatientNoteThreadChoices, required=False, allow_null=False
     )
+    reply_to = ExternalIdSerializerField(
+        queryset=PatientNotes.objects.all(),
+        write_only=True,
+        required=False,
+        allow_null=True,
+    )
+    reply_to_object = ReplyToPatientNoteSerializer(source="reply_to", read_only=True)
 
     def validate_empty_values(self, data):
         if not data.get("note", "").strip():
@@ -524,6 +546,10 @@ def validate_empty_values(self, data):
     def create(self, validated_data):
         if "thread" not in validated_data:
             raise serializers.ValidationError({"thread": "This field is required"})
+        if "consultation" not in validated_data:
+            raise serializers.ValidationError(
+                {"consultation": "This field is required"}
+            )
         user_type = User.REVERSE_TYPE_MAP[validated_data["created_by"].user_type]
         # If the user is a doctor and the note is being created in the home facility
         # then the user type is doctor else it is a remote specialist
@@ -536,6 +562,17 @@ def create(self, validated_data):
             # If the user is not a doctor then the user type is the same as the user type
             validated_data["user_type"] = user_type
 
+        if validated_data.get("reply_to"):
+            reply_to_note = validated_data["reply_to"]
+            if reply_to_note.thread != validated_data["thread"]:
+                raise serializers.ValidationError(
+                    "Reply to note should be in the same thread"
+                )
+            if reply_to_note.consultation != validated_data.get("consultation"):
+                raise serializers.ValidationError(
+                    "Reply to note should be in the same consultation"
+                )
+
         user = self.context["request"].user
         note = validated_data.get("note")
         with transaction.atomic():
@@ -584,6 +621,8 @@ class Meta:
             "modified_date",
             "last_edited_by",
             "last_edited_date",
+            "reply_to",
+            "reply_to_object",
         )
         read_only_fields = (
             "id",
diff --git a/care/facility/api/viewsets/patient.py b/care/facility/api/viewsets/patient.py
index a820331a92..4953ef54af 100644
--- a/care/facility/api/viewsets/patient.py
+++ b/care/facility/api/viewsets/patient.py
@@ -941,7 +941,9 @@ class PatientNotesViewSet(
 ):
     queryset = (
         PatientNotes.objects.all()
-        .select_related("facility", "patient", "created_by")
+        .select_related(
+            "facility", "patient", "created_by", "reply_to", "reply_to__created_by"
+        )
         .order_by("-created_date")
     )
     lookup_field = "external_id"
diff --git a/care/facility/migrations/0463_patientnotes_reply_to.py b/care/facility/migrations/0463_patientnotes_reply_to.py
new file mode 100644
index 0000000000..7b44acd71a
--- /dev/null
+++ b/care/facility/migrations/0463_patientnotes_reply_to.py
@@ -0,0 +1,25 @@
+# Generated by Django 5.1.1 on 2024-09-22 17:36
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("facility", "0462_facilityhubspoke"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="patientnotes",
+            name="reply_to",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name="replies",
+                to="facility.patientnotes",
+            ),
+        ),
+    ]
diff --git a/care/facility/models/patient.py b/care/facility/models/patient.py
index 6d328414ff..f635a773d4 100644
--- a/care/facility/models/patient.py
+++ b/care/facility/models/patient.py
@@ -799,6 +799,13 @@ class PatientNotes(FacilityBaseModel, ConsultationRelatedPermissionMixin):
         db_index=True,
         default=PatientNoteThreadChoices.DOCTORS,
     )
+    reply_to = models.ForeignKey(
+        "self",
+        on_delete=models.SET_NULL,
+        null=True,
+        blank=True,
+        related_name="replies",
+    )
     note = models.TextField(default="", blank=True)
 
     def get_related_consultation(self):
diff --git a/care/facility/tests/test_patient_api.py b/care/facility/tests/test_patient_api.py
index d4ea975c2f..c243c7a10b 100644
--- a/care/facility/tests/test_patient_api.py
+++ b/care/facility/tests/test_patient_api.py
@@ -27,6 +27,7 @@ class ExpectedPatientNoteKeys(Enum):
     LAST_EDITED_DATE = "last_edited_date"
     THREAD = "thread"
     USER_TYPE = "user_type"
+    REPLY_TO_OBJECT = "reply_to_object"
 
 
 class ExpectedFacilityKeys(Enum):
@@ -234,6 +235,48 @@ def test_patient_notes(self):
                 [item.value for item in ExpectedCreatedByObjectKeys],
             )
 
+    def test_patient_note_with_reply(self):
+        patient = self.patient
+        note = "How is the patient"
+        created_by = self.user
+
+        data = {
+            "facility": patient.facility or self.facility,
+            "note": note,
+            "thread": PatientNoteThreadChoices.DOCTORS,
+        }
+        self.client.force_authenticate(user=created_by)
+        response = self.client.post(
+            f"/api/v1/patient/{patient.external_id}/notes/", data=data
+        )
+        reply_data = {
+            "facility": patient.facility or self.facility,
+            "note": "Patient is doing fine",
+            "thread": PatientNoteThreadChoices.DOCTORS,
+            "reply_to": response.json()["id"],
+        }
+        reply_response = self.client.post(
+            f"/api/v1/patient/{patient.external_id}/notes/", data=reply_data
+        )
+
+        # Ensure the reply is created successfully
+        self.assertEqual(reply_response.status_code, status.HTTP_201_CREATED)
+
+        # Ensure the reply is posted on same thread
+        self.assertEqual(reply_response.json()["thread"], response.json()["thread"])
+
+        # Posting reply in other thread should fail
+        reply_response = self.client.post(
+            f"/api/v1/patient/{patient.external_id}/notes/",
+            {
+                "facility": patient.facility or self.facility,
+                "note": "Patient is doing fine",
+                "thread": PatientNoteThreadChoices.NURSES,
+                "reply_to": response.json()["id"],
+            },
+        )
+        self.assertEqual(reply_response.status_code, status.HTTP_400_BAD_REQUEST)
+
     def test_patient_note_edit(self):
         patientId = self.patient.external_id
         notes_list_response = self.client.get(