diff --git a/src/endpoints/statistics/index.ts b/src/endpoints/statistics/index.ts
index 96e558e..f171d9e 100644
--- a/src/endpoints/statistics/index.ts
+++ b/src/endpoints/statistics/index.ts
@@ -3,7 +3,7 @@ import filesize from 'filesize';
 
 import EsInstance from '../../ElasticSearchClientInstance';
 import { esBiospecimenIndex, esFileIndex, esParticipantIndex, esStudyIndex, esVariantIndex } from '../../esUtils';
-import { biospecimenIdKey, familyIdKey, fileIdKey, participantIdKey, studyIdKey } from '../../fieldsKeys';
+import { biospecimenIdKey, familyCountKey, fileIdKey, participantIdKey, studyIdKey } from '../../fieldsKeys';
 import { isInclude } from '../../projectUtils';
 
 export type Diagnosis = {
@@ -74,9 +74,9 @@ const fetchParticipantStats = async (client: Client): Promise<number> => {
 
 const fetchFamilyStats = async (client: Client): Promise<number> => {
     const { body } = await client.search({
-        index: esParticipantIndex,
+        index: esStudyIndex,
         body: {
-            aggs: { types_count: { value_count: { field: familyIdKey } } },
+            aggs: { types_count: { value_count: { field: familyCountKey } } },
         },
         size: 0,
     });
diff --git a/src/fieldsKeys.ts b/src/fieldsKeys.ts
index d3d63e8..3835628 100644
--- a/src/fieldsKeys.ts
+++ b/src/fieldsKeys.ts
@@ -3,7 +3,7 @@ export const fileIdKey = 'file_id';
 export const studyIdKey = 'study_id';
 export const participantIdKey = 'participant_id';
 export const biospecimenIdKey = 'sample_id';
-export const familyIdKey = 'family.family_id';
+export const familyCountKey = 'family_count';
 export const participantKey = 'fhir_id';
 export const participantFileKey = 'files.fhir_id';
 export const participantBiospecimenKey = 'files.biospecimens.fhir_id';