diff --git a/src/pages/patientView/timeline/legacy.js b/src/pages/patientView/timeline/legacy.js
index ef4eef0428d..901febd0ff9 100644
--- a/src/pages/patientView/timeline/legacy.js
+++ b/src/pages/patientView/timeline/legacy.js
@@ -167,6 +167,7 @@ export function buildTimeline(params, caseIds, patientInfo, clinicalDataMap, cas
     window.pvTimeline =
         window.pvTimeline
             .splitByClinicalAttributes("Treatment", ["TREATMENT_TYPE","SUBTYPE", "AGENT"])
+            .splitByClinicalAttributes("Diagnosis", ["SUBTYPE"])
             .collapseAll()
             .toggleTrackCollapse("Specimen")
             .enableTrackTooltips(false)