diff --git a/src/common.ts b/src/common.ts
index 7275a7d..4a723c4 100644
--- a/src/common.ts
+++ b/src/common.ts
@@ -67,6 +67,7 @@ export function main(
     .filter(([shop_name, shop]) => shop.calendar !== undefined)
     .forEach(([shop_name, shop], idx) => {
       calendar.addEventSource({
+        id: shop_name,
         url: '/calendar/ical/' + shop.calendar + '/public/basic.ics',
         format: 'ics',
         color: colors[idx],
@@ -91,6 +92,22 @@ export function main(
               );
             }
           }
+
+          // Add background event if resource has children
+          let tool_resource = calendar.getResourceById(eventData.resourceId);
+          let children = tool_resource?.getChildren();
+          if (tool_resource && children?.length) {
+            let new_event = {
+              ...eventData,
+              resourceIds: [
+                tool_resource.id,
+                ...children.map((resource) => resource.id),
+              ],
+              display: 'background',
+            };
+            calendar.addEvent(new_event, shop_name);
+          }
+
           return eventData;
         },
       });